diff --git a/lib/diver_down/web/bit_id.rb b/lib/diver_down/web/bit_id.rb
index 4b7f228..912544d 100644
--- a/lib/diver_down/web/bit_id.rb
+++ b/lib/diver_down/web/bit_id.rb
@@ -18,7 +18,7 @@ def bit_id_to_ids(bit_id)
           ids = []
           shift = 0
           while bit_id.positive?
-            if bit_id & 1
+            if (bit_id & 1) == 1
               ids.push(shift + 1)
             end
 
diff --git a/spec/diver_down/web/bit_id_spec.rb b/spec/diver_down/web/bit_id_spec.rb
index 2f7a59c..7d9e5e9 100644
--- a/spec/diver_down/web/bit_id_spec.rb
+++ b/spec/diver_down/web/bit_id_spec.rb
@@ -23,6 +23,13 @@
 
         expect(described_class.bit_id_to_ids(int_or)).to eq(ids)
       end
+
+      it 'converts given specific bit_id to id' do
+        id = 1922
+        bit_id = described_class.ids_to_bit_id([id])
+
+        expect(described_class.bit_id_to_ids(bit_id)).to eq([id])
+      end
     end
   end
 end