diff --git a/src/lib.rs b/src/lib.rs
index 7f1762e..9086300 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -11,6 +11,8 @@
 #[cfg(any(doc, test))]
 extern crate alloc;
 
+use core::num::*;
+
 #[cfg(any(doc, test))]
 use alloc::string::ToString;
 
@@ -79,39 +81,39 @@ impl ToArrayString for bool {
 impl_float!(ToArrayString<16> for f32);
 impl_float!(ToArrayString<24> for f64);
 
-impl_int!(ToArrayString<3> for u8);
-impl_int!(ToArrayString<4> for i8);
-impl_int!(ToArrayString<5> for u16);
-impl_int!(ToArrayString<6> for i16);
-impl_int!(ToArrayString<10> for u32);
-impl_int!(ToArrayString<11> for i32);
-impl_int!(ToArrayString<20> for u64);
-impl_int!(ToArrayString<21> for i64);
-impl_int!(ToArrayString<39> for u128);
-impl_int!(ToArrayString<40> for i128);
+impl_int!(ToArrayString<3> for (u8, NonZeroU8));
+impl_int!(ToArrayString<4> for (i8, NonZeroI8));
+impl_int!(ToArrayString<5> for (u16, NonZeroU16));
+impl_int!(ToArrayString<6> for (i16, NonZeroI16));
+impl_int!(ToArrayString<10> for (u32, NonZeroU32));
+impl_int!(ToArrayString<11> for (i32, NonZeroI32));
+impl_int!(ToArrayString<20> for (u64, NonZeroU64));
+impl_int!(ToArrayString<21> for (i64, NonZeroI64));
+impl_int!(ToArrayString<39> for (u128, NonZeroU128));
+impl_int!(ToArrayString<40> for (i128, NonZeroI128));
 
 #[cfg(target_pointer_width = "16")]
 mod usize_impls {
     use super::*;
 
-    impl_int!(ToArrayString<5> for usize);
-    impl_int!(ToArrayString<6> for isize);
+    impl_int!(ToArrayString<5> for (usize, NonZeroUsize));
+    impl_int!(ToArrayString<6> for (isize, NonZeroIsize));
 }
 
 #[cfg(target_pointer_width = "32")]
 mod usize_impls {
     use super::*;
 
-    impl_int!(ToArrayString<10> for usize);
-    impl_int!(ToArrayString<11> for isize);
+    impl_int!(ToArrayString<10> for (usize, NonZeroUsize));
+    impl_int!(ToArrayString<11> for (isize, NonZeroIsize));
 }
 
 #[cfg(target_pointer_width = "64")]
 mod usize_impls {
     use super::*;
 
-    impl_int!(ToArrayString<20> for usize);
-    impl_int!(ToArrayString<21> for isize);
+    impl_int!(ToArrayString<20> for (usize, NonZeroUsize));
+    impl_int!(ToArrayString<21> for (isize, NonZeroIsize));
 }
 
 #[cfg(test)]
@@ -124,4 +126,18 @@ mod tests {
     }
 
     crate::macros::generate_test!(u8, i8, u16, i16, u32, i32, u64, i64, u128, i128, usize, isize);
+    crate::macros::generate_test!(
+        NonZeroU8,
+        NonZeroI8,
+        NonZeroU16,
+        NonZeroI16,
+        NonZeroU32,
+        NonZeroI32,
+        NonZeroU64,
+        NonZeroI64,
+        NonZeroU128,
+        NonZeroI128,
+        NonZeroUsize,
+        NonZeroIsize
+    );
 }
diff --git a/src/macros.rs b/src/macros.rs
index f05bd35..4fb4a02 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -13,7 +13,7 @@ gen_fmt_to_buf!(fmt_int_to_buf(itoa::Integer));
 gen_fmt_to_buf!(fmt_float_to_buf(ryu::Float));
 
 macro_rules! impl_int {
-    (ToArrayString<$len:literal> for $type:ty) => {
+    (ToArrayString<$len:literal> for ($type:ty, $non_zero:ty)) => {
         impl ToArrayString for $type {
             const MAX_LENGTH: usize = $len;
             type ArrayString = ArrayString<$len>;
@@ -24,7 +24,7 @@ macro_rules! impl_int {
             }
         }
 
-        impl ToArrayString for core::num::NonZero<$type> {
+        impl ToArrayString for $non_zero {
             const MAX_LENGTH: usize = $len;
             type ArrayString = ArrayString<$len>;
 
@@ -54,9 +54,8 @@ macro_rules! generate_test {
     ($($type:ident),*) => {
         paste::paste!($(
             #[test]
-            fn [<check_ $type>]() {
+            fn [<check_ $type:lower>]() {
                 test_impl($type::MIN, $type::MAX);
-                test_impl(core::num::NonZero::<$type>::MIN, core::num::NonZero::<$type>::MAX);
             }
         )*);
     };