diff --git a/code/__DEFINES/dcs/signals/signals_object.dm b/code/__DEFINES/dcs/signals/signals_object.dm
index 01145cd32ea..d926cc6d5df 100644
--- a/code/__DEFINES/dcs/signals/signals_object.dm
+++ b/code/__DEFINES/dcs/signals/signals_object.dm
@@ -529,3 +529,8 @@
 
 /// from /datum/component/dart_insert/on_reskin()
 #define COMSIG_DART_INSERT_PARENT_RESKINNED "dart_insert_parent_reskinned"
+
+/// Sent from /obj/item/update_weight_class(). (old_w_class, new_w_class)
+#define COMSIG_ITEM_WEIGHT_CLASS_CHANGED "item_weight_class_changed"
+/// Sent from /obj/item/update_weight_class(), to it's loc. (obj/item/changed_item, old_w_class, new_w_class)
+#define COMSIG_ATOM_CONTENTS_WEIGHT_CLASS_CHANGED "atom_contents_weight_class_changed"
diff --git a/code/__DEFINES/inventory.dm b/code/__DEFINES/inventory.dm
index 23c7428625d..b513aaa86ed 100644
--- a/code/__DEFINES/inventory.dm
+++ b/code/__DEFINES/inventory.dm
@@ -14,6 +14,9 @@
 /// Essentially means it cannot be picked up or placed in an inventory, (e.g. mech parts, safe)
 #define WEIGHT_CLASS_GIGANTIC 6
 
+/// Weight class that can fit in pockets
+#define POCKET_WEIGHT_CLASS WEIGHT_CLASS_SMALL
+
 //Inventory depth: limits how many nested storage items you can access directly.
 //1: stuff in mob, 2: stuff in backpack, 3: stuff in box in backpack, etc
 #define INVENTORY_DEPTH 3
diff --git a/code/datums/components/customizable_reagent_holder.dm b/code/datums/components/customizable_reagent_holder.dm
index bd88508bec0..fd1b8a2ac64 100644
--- a/code/datums/components/customizable_reagent_holder.dm
+++ b/code/datums/components/customizable_reagent_holder.dm
@@ -206,7 +206,7 @@
 	if(isitem(atom_parent))
 		var/obj/item/item_parent = atom_parent
 		if(ingredient.w_class > item_parent.w_class)
-			item_parent.w_class = ingredient.w_class
+			item_parent.update_weight_class(ingredient.w_class)
 	atom_parent.name = "[custom_adjective()] [custom_type()] [initial(atom_parent.name)]"
 	SEND_SIGNAL(atom_parent, COMSIG_ATOM_CUSTOMIZED, ingredient)
 	SEND_SIGNAL(ingredient, COMSIG_ITEM_USED_AS_INGREDIENT, atom_parent)
diff --git a/code/datums/components/transforming.dm b/code/datums/components/transforming.dm
index e51c784657b..5276f45dc0a 100644
--- a/code/datums/components/transforming.dm
+++ b/code/datums/components/transforming.dm
@@ -212,7 +212,7 @@
 		source.attack_verb_simple = attack_verb_simple_on
 
 	source.hitsound = hitsound_on
-	source.w_class = w_class_on
+	source.update_weight_class(w_class_on)
 	source.icon_state = "[source.icon_state]_on"
 	if(inhand_icon_change && source.inhand_icon_state)
 		source.inhand_icon_state = "[source.inhand_icon_state]_on"
@@ -241,7 +241,7 @@
 		source.attack_verb_simple = attack_verb_simple_off
 
 	source.hitsound = initial(source.hitsound)
-	source.w_class = initial(source.w_class)
+	source.update_weight_class(initial(source.w_class))
 	source.icon_state = initial(source.icon_state)
 	source.inhand_icon_state = initial(source.inhand_icon_state)
 	if(ismob(source.loc))
diff --git a/code/datums/storage/storage.dm b/code/datums/storage/storage.dm
index 42fad48509d..a1a4180132f 100644
--- a/code/datums/storage/storage.dm
+++ b/code/datums/storage/storage.dm
@@ -207,6 +207,7 @@
 	RegisterSignal(parent, COMSIG_ATOM_EXAMINE_MORE, PROC_REF(handle_extra_examination))
 	RegisterSignal(parent, COMSIG_OBJ_DECONSTRUCT, PROC_REF(on_deconstruct))
 	RegisterSignal(parent, COMSIG_ATOM_EMP_ACT, PROC_REF(on_emp_act))
+	RegisterSignal(parent, COMSIG_ATOM_CONTENTS_WEIGHT_CLASS_CHANGED, PROC_REF(contents_changed_w_class))
 
 /**
  * Sets where items are physically being stored in the case it shouldn't be on the parent.
@@ -1092,3 +1093,14 @@ GLOBAL_LIST_EMPTY(cached_storage_typecaches)
 	var/matrix/old_matrix = parent.transform
 	animate(parent, time = 1.5, loop = 0, transform = parent.transform.Scale(1.07, 0.9))
 	animate(time = 2, transform = old_matrix)
+
+/// Signal proc for [COMSIG_ATOM_CONTENTS_WEIGHT_CLASS_CHANGED] to drop items out of our storage if they're suddenly too heavy.
+/datum/storage/proc/contents_changed_w_class(datum/source, obj/item/changed, old_w_class, new_w_class)
+	SIGNAL_HANDLER
+
+	if(new_w_class <= max_specific_storage && new_w_class + get_total_weight() <= max_total_storage)
+		return
+	if(!attempt_remove(changed, parent.drop_location()))
+		return
+
+	changed.visible_message(span_warning("[changed] falls out of [parent]!"), vision_distance = COMBAT_MESSAGE_RANGE)
diff --git a/code/datums/storage/subtypes/fish_case.dm b/code/datums/storage/subtypes/fish_case.dm
index dbbb15f47eb..82733d37ad9 100644
--- a/code/datums/storage/subtypes/fish_case.dm
+++ b/code/datums/storage/subtypes/fish_case.dm
@@ -24,25 +24,11 @@
 	var/obj/item/item_parent = parent
 	if(arrived.w_class <= item_parent.w_class)
 		return
-	item_parent.w_class = arrived.w_class
-	// Since we're changing weight class we need to check if our storage's loc's storage can still hold us
-	// in the future we need a generic solution to this to solve a bunch of other exploits
-	var/datum/storage/loc_storage = item_parent.loc.atom_storage
-	if(!isnull(loc_storage) && !loc_storage.can_insert(item_parent))
-		item_parent.forceMove(item_parent.loc.drop_location())
-		item_parent.visible_message(span_warning("[item_parent] spills out of [item_parent.loc] as it expands to hold [arrived]!"), vision_distance = 1)
-		return
-
-	if(isliving(item_parent.loc))
-		var/mob/living/living_loc = item_parent.loc
-		if((living_loc.get_slot_by_item(item_parent) & (ITEM_SLOT_RPOCKET|ITEM_SLOT_LPOCKET)) && item_parent.w_class > WEIGHT_CLASS_SMALL)
-			item_parent.forceMove(living_loc.drop_location())
-			to_chat(living_loc, span_warning("[item_parent] drops out of your pockets as it expands to hold [arrived]!"))
-		return
+	item_parent.update_weight_class(arrived.w_class)
 
 /datum/storage/fish_case/handle_exit(datum/source, obj/item/gone)
 	. = ..()
 	if(!isitem(parent) || !istype(gone))
 		return
 	var/obj/item/item_parent = parent
-	item_parent.w_class = initial(item_parent.w_class)
+	item_parent.update_weight_class(initial(item_parent.w_class))
diff --git a/code/game/objects/items.dm b/code/game/objects/items.dm
index dcdcac16cf8..9097b18d64a 100644
--- a/code/game/objects/items.dm
+++ b/code/game/objects/items.dm
@@ -1755,3 +1755,24 @@
 
 /obj/item/animate_atom_living(mob/living/owner)
 	new /mob/living/simple_animal/hostile/mimic/copy(drop_location(), src, owner)
+
+/**
+ * Used to update the weight class of the item in a way that other atoms can react to the change.
+ *
+ * Arguments:
+ * * new_w_class - The new weight class of the item.
+ *
+ * Returns:
+ * * TRUE if weight class was successfully updated
+ * * FALSE otherwise
+ */
+/obj/item/proc/update_weight_class(new_w_class)
+	if(w_class == new_w_class)
+		return FALSE
+
+	var/old_w_class = w_class
+	w_class = new_w_class
+	SEND_SIGNAL(src, COMSIG_ITEM_WEIGHT_CLASS_CHANGED, old_w_class, new_w_class)
+	if(!isnull(loc))
+		SEND_SIGNAL(loc, COMSIG_ATOM_CONTENTS_WEIGHT_CLASS_CHANGED, src, old_w_class, new_w_class)
+	return TRUE
diff --git a/code/game/objects/items/dualsaber.dm b/code/game/objects/items/dualsaber.dm
index 2d32485f31f..0e8adaadd9f 100644
--- a/code/game/objects/items/dualsaber.dm
+++ b/code/game/objects/items/dualsaber.dm
@@ -61,7 +61,7 @@
 		if(user.dna.check_mutation(/datum/mutation/human/hulk))
 			to_chat(user, span_warning("You lack the grace to wield this!"))
 			return COMPONENT_TWOHANDED_BLOCK_WIELD
-	w_class = w_class_on
+	update_weight_class(w_class_on)
 	hitsound = 'sound/weapons/blade1.ogg'
 	START_PROCESSING(SSobj, src)
 	set_light_on(TRUE)
@@ -69,7 +69,7 @@
 /// Triggered on unwield of two handed item
 /// switch hitsounds
 /obj/item/dualsaber/proc/on_unwield(obj/item/source, mob/living/carbon/user)
-	w_class = initial(w_class)
+	update_weight_class(initial(w_class))
 	hitsound = SFX_SWING_HIT
 	STOP_PROCESSING(SSobj, src)
 	set_light_on(FALSE)
diff --git a/code/game/objects/items/stacks/stack.dm b/code/game/objects/items/stacks/stack.dm
index 7a025bc6bcc..18a95cd77d3 100644
--- a/code/game/objects/items/stacks/stack.dm
+++ b/code/game/objects/items/stacks/stack.dm
@@ -196,11 +196,11 @@
 
 /obj/item/stack/proc/update_weight()
 	if(amount <= (max_amount * (1/3)))
-		w_class = clamp(full_w_class-2, WEIGHT_CLASS_TINY, full_w_class)
+		update_weight_class(clamp(full_w_class-2, WEIGHT_CLASS_TINY, full_w_class))
 	else if (amount <= (max_amount * (2/3)))
-		w_class = clamp(full_w_class-1, WEIGHT_CLASS_TINY, full_w_class)
+		update_weight_class(clamp(full_w_class-1, WEIGHT_CLASS_TINY, full_w_class))
 	else
-		w_class = full_w_class
+		update_weight_class(full_w_class)
 
 /obj/item/stack/update_icon_state()
 	if(novariants)
diff --git a/code/game/objects/items/stacks/wrap.dm b/code/game/objects/items/stacks/wrap.dm
index e4b29b005a3..8521ee7c55f 100644
--- a/code/game/objects/items/stacks/wrap.dm
+++ b/code/game/objects/items/stacks/wrap.dm
@@ -135,7 +135,7 @@
 			item.forceMove(parcel)
 			var/size = round(item.w_class)
 			parcel.name = "[weight_class_to_text(size)] parcel"
-			parcel.w_class = size
+			parcel.update_weight_class(size)
 			size = min(size, 5)
 			parcel.base_icon_state = "deliverypackage[size]"
 			parcel.update_icon()
diff --git a/code/game/objects/items/tanks/tanks.dm b/code/game/objects/items/tanks/tanks.dm
index e198f7d75d7..a1127384c61 100644
--- a/code/game/objects/items/tanks/tanks.dm
+++ b/code/game/objects/items/tanks/tanks.dm
@@ -460,7 +460,7 @@
 	tank_assembly = assembly //Tell the tank about its assembly part
 	assembly.master = src //Tell the assembly about its new owner
 	assembly.on_attach()
-	w_class = WEIGHT_CLASS_BULKY
+	update_weight_class(WEIGHT_CLASS_BULKY)
 
 	balloon_alert(user, "bomb assembled")
 	update_appearance(UPDATE_OVERLAYS)
@@ -474,7 +474,7 @@
 	user.put_in_hands(tank_assembly)
 	tank_assembly.master = null
 	tank_assembly = null
-	w_class = initial(w_class)
+	update_weight_class(initial(w_class))
 	update_appearance(UPDATE_OVERLAYS)
 
 /// Ignites the contents of the tank. Called when receiving a signal if the tank is welded and has an igniter attached.
diff --git a/code/game/objects/items/tools/spess_knife.dm b/code/game/objects/items/tools/spess_knife.dm
index 0b0061de7a4..9fd5dbb0158 100644
--- a/code/game/objects/items/tools/spess_knife.dm
+++ b/code/game/objects/items/tools/spess_knife.dm
@@ -60,10 +60,10 @@
 		mistake_occured = TRUE
 
 	if(isnull(tool_behaviour))
-		w_class = WEIGHT_CLASS_TINY
+		update_weight_class(WEIGHT_CLASS_TINY)
 		balloon_alert(user, "folded")
 	else
-		w_class = WEIGHT_CLASS_SMALL
+		update_weight_class(WEIGHT_CLASS_SMALL)
 		balloon_alert(user, mistake_occured ? "oops! [tool_behaviour] out" : "[tool_behaviour] out")
 
 	update_tool_parameters()
diff --git a/code/game/objects/structures/crates_lockers/closets/bodybag.dm b/code/game/objects/structures/crates_lockers/closets/bodybag.dm
index bfed8bea979..38482fcfd9b 100644
--- a/code/game/objects/structures/crates_lockers/closets/bodybag.dm
+++ b/code/game/objects/structures/crates_lockers/closets/bodybag.dm
@@ -171,7 +171,7 @@
 		if(A_is_item.w_class < max_weight_of_contents)
 			continue
 		max_weight_of_contents = A_is_item.w_class
-	folding_bodybag.w_class = max_weight_of_contents
+	folding_bodybag.update_weight_class(max_weight_of_contents)
 	the_folder.put_in_hands(folding_bodybag)
 
 /// Environmental bags. They protect against bad weather.
diff --git a/code/modules/antagonists/heretic/items/forbidden_book.dm b/code/modules/antagonists/heretic/items/forbidden_book.dm
index ad6bc388800..06f091c77e7 100644
--- a/code/modules/antagonists/heretic/items/forbidden_book.dm
+++ b/code/modules/antagonists/heretic/items/forbidden_book.dm
@@ -39,11 +39,11 @@
 	if(book_open)
 		close_animation()
 		RemoveElement(/datum/element/heretic_focus)
-		w_class = WEIGHT_CLASS_SMALL
+		update_weight_class(WEIGHT_CLASS_SMALL)
 	else
 		open_animation()
 		AddElement(/datum/element/heretic_focus)
-		w_class = WEIGHT_CLASS_NORMAL
+		update_weight_class(WEIGHT_CLASS_NORMAL)
 
 /obj/item/codex_cicatrix/afterattack(atom/target, mob/user, proximity_flag, click_parameters)
 	. = ..()
diff --git a/code/modules/detectivework/evidence.dm b/code/modules/detectivework/evidence.dm
index e22235084f9..c10648e3315 100644
--- a/code/modules/detectivework/evidence.dm
+++ b/code/modules/detectivework/evidence.dm
@@ -22,7 +22,7 @@
 /obj/item/evidencebag/Exited(atom/movable/gone, direction)
 	. = ..()
 	cut_overlays()
-	w_class = initial(w_class)
+	update_weight_class(initial(w_class))
 	icon_state = initial(icon_state)
 	desc = initial(desc)
 
@@ -78,7 +78,7 @@
 
 	desc = "An evidence bag containing [I]. [I.desc]"
 	I.forceMove(src)
-	w_class = I.w_class
+	update_weight_class(I.w_class)
 	return 1
 
 /obj/item/evidencebag/attack_self(mob/user)
@@ -88,7 +88,7 @@
 		span_hear("You hear someone rustle around in a plastic bag, and remove something."))
 		cut_overlays() //remove the overlays
 		user.put_in_hands(I)
-		w_class = WEIGHT_CLASS_TINY
+		update_weight_class(WEIGHT_CLASS_TINY)
 		icon_state = "evidenceobj"
 		desc = "An empty evidence bag."
 
diff --git a/code/modules/fishing/fish/_fish.dm b/code/modules/fishing/fish/_fish.dm
index 90fb2afc796..00c52eb338a 100644
--- a/code/modules/fishing/fish/_fish.dm
+++ b/code/modules/fishing/fish/_fish.dm
@@ -204,20 +204,20 @@
 	size = new_size
 	switch(size)
 		if(0 to FISH_SIZE_TINY_MAX)
-			w_class = WEIGHT_CLASS_TINY
+			update_weight_class(WEIGHT_CLASS_TINY)
 			inhand_icon_state = "fish_small"
 		if(FISH_SIZE_TINY_MAX to FISH_SIZE_SMALL_MAX)
 			inhand_icon_state = "fish_small"
-			w_class = WEIGHT_CLASS_SMALL
+			update_weight_class(WEIGHT_CLASS_SMALL)
 		if(FISH_SIZE_SMALL_MAX to FISH_SIZE_NORMAL_MAX)
 			inhand_icon_state = "fish_normal"
-			w_class = WEIGHT_CLASS_NORMAL
+			update_weight_class(WEIGHT_CLASS_NORMAL)
 		if(FISH_SIZE_NORMAL_MAX to FISH_SIZE_BULKY_MAX)
 			inhand_icon_state = "fish_bulky"
-			w_class = WEIGHT_CLASS_BULKY
+			update_weight_class(WEIGHT_CLASS_BULKY)
 		if(FISH_SIZE_BULKY_MAX to INFINITY)
 			inhand_icon_state = "fish_huge"
-			w_class = WEIGHT_CLASS_HUGE
+			update_weight_class(WEIGHT_CLASS_HUGE)
 	if(fillet_type)
 		var/init_fillets = initial(num_fillets)
 		var/amount = max(round(init_fillets * size / FISH_FILLET_NUMBER_SIZE_DIVISOR, 1), 1)
diff --git a/code/modules/food_and_drinks/plate.dm b/code/modules/food_and_drinks/plate.dm
index 1df1d7c24bb..4ae6bf19e1d 100644
--- a/code/modules/food_and_drinks/plate.dm
+++ b/code/modules/food_and_drinks/plate.dm
@@ -70,7 +70,7 @@
 	update_appearance()
 	// If the incoming item is the same weight class as the plate, bump us up a class
 	if(item_to_plate.w_class == w_class)
-		w_class += 1
+		update_weight_class(w_class + 1)
 
 ///This proc cleans up any signals on the item when it is removed from a plate, and ensures it has the correct state again.
 /obj/item/plate/proc/ItemRemovedFromPlate(obj/item/removed_item)
@@ -85,12 +85,14 @@
 	removed_item.pixel_z = 0
 	// We need to ensure the weight class is accurate now that we've lost something
 	// that may or may not have been of equal weight
-	w_class = initial(w_class)
+	var/new_w_class = initial(w_class)
 	for(var/obj/item/on_board in src)
 		if(on_board.w_class == w_class)
-			w_class += 1
+			new_w_class += 1
 			break
 
+	update_weight_class(new_w_class)
+
 ///This proc is called by signals that remove the food from the plate.
 /obj/item/plate/proc/ItemMoved(obj/item/moved_item, atom/OldLoc, Dir, Forced)
 	SIGNAL_HANDLER
diff --git a/code/modules/hallucination/inhand_fake_item.dm b/code/modules/hallucination/inhand_fake_item.dm
index efea8b309e2..cb787d217e1 100644
--- a/code/modules/hallucination/inhand_fake_item.dm
+++ b/code/modules/hallucination/inhand_fake_item.dm
@@ -43,7 +43,7 @@
 	hallucinated_item.desc = initial(template_item_type.desc)
 	hallucinated_item.icon = initial(template_item_type.icon)
 	hallucinated_item.icon_state = initial(template_item_type.icon_state)
-	hallucinated_item.w_class = initial(template_item_type.w_class) // Not strictly necessary, but keen eyed people will notice
+	hallucinated_item.update_weight_class(initial(template_item_type.w_class)) // Not strictly necessary, but keen eyed people will notice
 
 	return hallucinated_item
 
diff --git a/code/modules/mining/equipment/explorer_gear.dm b/code/modules/mining/equipment/explorer_gear.dm
index 38df199b251..10ba871176f 100644
--- a/code/modules/mining/equipment/explorer_gear.dm
+++ b/code/modules/mining/equipment/explorer_gear.dm
@@ -90,7 +90,7 @@
 /obj/item/clothing/mask/gas/explorer/adjustmask(mob/user)
 	. = ..()
 	// adjusted = out of the way = smaller = can fit in boxes
-	w_class = mask_adjusted ? WEIGHT_CLASS_SMALL : WEIGHT_CLASS_NORMAL
+	update_weight_class(mask_adjusted ? WEIGHT_CLASS_SMALL : WEIGHT_CLASS_NORMAL)
 	inhand_icon_state = mask_adjusted ? "[initial(inhand_icon_state)]_up" : initial(inhand_icon_state)
 	if(user)
 		user.update_held_items()
@@ -353,4 +353,3 @@
 	desc = "An armoured hood for exploring harsh environments."
 	icon_state = "explorer_syndicate"
 	armor_type = /datum/armor/hooded_explorer_syndicate
-
diff --git a/code/modules/mining/equipment/mining_tools.dm b/code/modules/mining/equipment/mining_tools.dm
index 9fdb772c4bc..2c8a6af7864 100644
--- a/code/modules/mining/equipment/mining_tools.dm
+++ b/code/modules/mining/equipment/mining_tools.dm
@@ -257,7 +257,7 @@
 			tool_behaviour = TOOL_WRENCH
 			sharpness = NONE
 			toolspeed = 0.75
-			w_class = WEIGHT_CLASS_SMALL
+			update_weight_class(WEIGHT_CLASS_SMALL)
 			usesound = 'sound/items/ratchet.ogg'
 			attack_verb_continuous = list("bashes", "bludgeons", "thrashes", "whacks")
 			attack_verb_simple = list("bash", "bludgeon", "thrash", "whack")
@@ -265,7 +265,7 @@
 			tool_behaviour = TOOL_SHOVEL
 			sharpness = SHARP_EDGED
 			toolspeed = 0.25
-			w_class = WEIGHT_CLASS_NORMAL
+			update_weight_class(WEIGHT_CLASS_NORMAL)
 			usesound = 'sound/effects/shovel_dig.ogg'
 			attack_verb_continuous = list("slashes", "impales", "stabs", "slices")
 			attack_verb_simple = list("slash", "impale", "stab", "slice")
@@ -273,7 +273,7 @@
 			tool_behaviour = TOOL_MINING
 			sharpness = SHARP_POINTY
 			toolspeed = 0.5
-			w_class = WEIGHT_CLASS_NORMAL
+			update_weight_class(WEIGHT_CLASS_NORMAL)
 			usesound = 'sound/effects/picaxe1.ogg'
 			attack_verb_continuous = list("hits", "pierces", "slices", "attacks")
 			attack_verb_simple = list("hit", "pierce", "slice", "attack")
diff --git a/code/modules/mob/living/carbon/human/_species.dm b/code/modules/mob/living/carbon/human/_species.dm
index 379248c7438..14a0735cd4f 100644
--- a/code/modules/mob/living/carbon/human/_species.dm
+++ b/code/modules/mob/living/carbon/human/_species.dm
@@ -871,7 +871,7 @@ GLOBAL_LIST_EMPTY(features_by_species)
 	if(!(I.slot_flags & slot))
 		var/excused = FALSE
 		// Anything that's small or smaller can fit into a pocket by default
-		if((slot & (ITEM_SLOT_RPOCKET|ITEM_SLOT_LPOCKET)) && I.w_class <= WEIGHT_CLASS_SMALL)
+		if((slot & (ITEM_SLOT_RPOCKET|ITEM_SLOT_LPOCKET)) && I.w_class <= POCKET_WEIGHT_CLASS)
 			excused = TRUE
 		else if(slot & (ITEM_SLOT_SUITSTORE|ITEM_SLOT_BACKPACK|ITEM_SLOT_HANDS))
 			excused = TRUE
diff --git a/code/modules/mob/living/carbon/human/init_signals.dm b/code/modules/mob/living/carbon/human/init_signals.dm
index 6e16781a59e..dc5ce972105 100644
--- a/code/modules/mob/living/carbon/human/init_signals.dm
+++ b/code/modules/mob/living/carbon/human/init_signals.dm
@@ -8,6 +8,8 @@
 	RegisterSignals(src, list(SIGNAL_ADDTRAIT(TRAIT_FAT), SIGNAL_REMOVETRAIT(TRAIT_FAT)), PROC_REF(on_fat))
 	RegisterSignals(src, list(SIGNAL_ADDTRAIT(TRAIT_NOHUNGER), SIGNAL_REMOVETRAIT(TRAIT_NOHUNGER)), PROC_REF(on_nohunger))
 
+	RegisterSignal(src, COMSIG_ATOM_CONTENTS_WEIGHT_CLASS_CHANGED, PROC_REF(check_pocket_weght))
+
 /// Gaining or losing [TRAIT_UNKNOWN] updates our name and our sechud
 /mob/living/carbon/human/proc/on_unknown_trait(datum/source)
 	SIGNAL_HANDLER
@@ -63,3 +65,19 @@
 	else
 		hud_used?.hunger?.update_appearance()
 		mob_mood?.update_nutrition_moodlets()
+
+/// Signal proc for [COMSIG_ATOM_CONTENTS_WEIGHT_CLASS_CHANGED] to check if an item is suddenly too heavy for our pockets
+/mob/living/carbon/human/proc/check_pocket_weght(datum/source, obj/item/changed, old_w_class, new_w_class)
+	SIGNAL_HANDLER
+	if(changed != r_store && changed != l_store)
+		return
+	if(new_w_class <= POCKET_WEIGHT_CLASS)
+		return
+	if(!dropItemToGround(changed, force = TRUE))
+		return
+	visible_message(
+		span_warning("[changed] falls out of [src]'s pockets!"),
+		span_warning("[changed] falls out of your pockets!"),
+		vision_distance = COMBAT_MESSAGE_RANGE,
+	)
+	playsound(src, SFX_RUSTLE, 50, TRUE, -5, frequency = 0.8)
diff --git a/code/modules/mob/living/inhand_holder.dm b/code/modules/mob/living/inhand_holder.dm
index b4c9fbd34aa..808c8973963 100644
--- a/code/modules/mob/living/inhand_holder.dm
+++ b/code/modules/mob/living/inhand_holder.dm
@@ -20,7 +20,7 @@
 		righthand_file = rh_icon
 	if(worn_slot_flags)
 		slot_flags = worn_slot_flags
-	w_class = M.held_w_class
+	update_weight_class(M.held_w_class)
 	deposit(M)
 	. = ..()
 
diff --git a/code/modules/mod/modules/modules_antag.dm b/code/modules/mod/modules/modules_antag.dm
index 2462f62a3d3..bd96c5aec5f 100644
--- a/code/modules/mod/modules/modules_antag.dm
+++ b/code/modules/mod/modules/modules_antag.dm
@@ -460,10 +460,10 @@
 
 /obj/item/mod/module/plate_compression/on_install()
 	old_size = mod.w_class
-	mod.w_class = new_size
+	mod.update_weight_class(new_size)
 
 /obj/item/mod/module/plate_compression/on_uninstall(deleting = FALSE)
-	mod.w_class = old_size
+	mod.update_weight_class(old_size)
 	old_size = null
 	if(!mod.loc)
 		return
diff --git a/code/modules/modular_computers/computers/item/laptop.dm b/code/modules/modular_computers/computers/item/laptop.dm
index d3b620cdfc9..3bf46f16d1b 100644
--- a/code/modules/modular_computers/computers/item/laptop.dm
+++ b/code/modules/modular_computers/computers/item/laptop.dm
@@ -104,12 +104,12 @@
 	if(screen_on)
 		to_chat(user, span_notice("You close \the [src]."))
 		slowdown = initial(slowdown)
-		w_class = initial(w_class)
+		update_weight_class(initial(w_class))
 		drag_slowdown = initial(drag_slowdown)
 	else
 		to_chat(user, span_notice("You open \the [src]."))
 		slowdown = slowdown_open
-		w_class = w_class_open
+		update_weight_class(w_class_open)
 		drag_slowdown = slowdown_open
 	if(isliving(loc))
 		var/mob/living/localmob = loc
diff --git a/code/modules/projectiles/guns/ballistic.dm b/code/modules/projectiles/guns/ballistic.dm
index a151402d517..bf4b37dbe9b 100644
--- a/code/modules/projectiles/guns/ballistic.dm
+++ b/code/modules/projectiles/guns/ballistic.dm
@@ -481,7 +481,7 @@
 ///Installs a new suppressor, assumes that the suppressor is already in the contents of src
 /obj/item/gun/ballistic/proc/install_suppressor(obj/item/suppressor/S)
 	suppressed = S
-	w_class += S.w_class //so pistols do not fit in pockets when suppressed
+	update_weight_class(w_class + S.w_class) //so pistols do not fit in pockets when suppressed
 	update_appearance()
 
 /obj/item/gun/ballistic/clear_suppressor()
@@ -489,7 +489,7 @@
 		return
 	if(isitem(suppressed))
 		var/obj/item/I = suppressed
-		w_class -= I.w_class
+		update_weight_class(w_class - I.w_class)
 	return ..()
 
 /obj/item/gun/ballistic/AltClick(mob/user)
@@ -662,7 +662,7 @@ GLOBAL_LIST_INIT(gun_saw_types, typecacheof(list(
 		if(handle_modifications)
 			name = "sawn-off [src.name]"
 			desc = sawn_desc
-			w_class = WEIGHT_CLASS_NORMAL
+			update_weight_class(WEIGHT_CLASS_NORMAL)
 			//The file might not have a "gun" icon, let's prepare for this
 			lefthand_file = 'icons/mob/inhands/weapons/guns_lefthand.dmi'
 			righthand_file = 'icons/mob/inhands/weapons/guns_righthand.dmi'
diff --git a/code/modules/unit_tests/_unit_tests.dm b/code/modules/unit_tests/_unit_tests.dm
index 72be3076397..892540192b3 100644
--- a/code/modules/unit_tests/_unit_tests.dm
+++ b/code/modules/unit_tests/_unit_tests.dm
@@ -255,6 +255,7 @@
 #include "station_trait_tests.dm"
 #include "status_effect_ticks.dm"
 #include "stomach.dm"
+#include "storage.dm"
 #include "strange_reagent.dm"
 #include "strippable.dm"
 #include "stuns.dm"
diff --git a/code/modules/unit_tests/storage.dm b/code/modules/unit_tests/storage.dm
new file mode 100644
index 00000000000..82ac035ed7e
--- /dev/null
+++ b/code/modules/unit_tests/storage.dm
@@ -0,0 +1,22 @@
+/// Test storage datums
+/datum/unit_test/storage
+
+/datum/unit_test/storage/Run()
+	var/obj/item/big_thing = allocate(__IMPLIED_TYPE__, run_loc_floor_bottom_left)
+	big_thing.w_class = WEIGHT_CLASS_BULKY
+	var/obj/item/small_thing =  allocate(__IMPLIED_TYPE__, run_loc_floor_bottom_left)
+	small_thing.w_class = WEIGHT_CLASS_SMALL
+
+	var/obj/item/storage/backpack/storage_item =  allocate(__IMPLIED_TYPE__, run_loc_floor_bottom_left)
+
+	storage_item.atom_storage.attempt_insert(big_thing)
+	TEST_ASSERT_NOTEQUAL(big_thing.loc, storage_item, "A bulky item should have failed to insert into a backpack")
+
+	storage_item.atom_storage.attempt_insert(small_thing)
+	TEST_ASSERT_EQUAL(small_thing.loc, storage_item, "A small item should have successfully inserted into a backpack")
+
+	small_thing.update_weight_class(WEIGHT_CLASS_NORMAL)
+	TEST_ASSERT_EQUAL(small_thing.loc, storage_item, "A small item changed into normal size should not have ejected from the backpack")
+
+	small_thing.update_weight_class(WEIGHT_CLASS_BULKY)
+	TEST_ASSERT_NOTEQUAL(small_thing.loc, storage_item, "A small item changed back into bulky size should have ejected from the backpack")