diff --git a/specs/simple-serialize.md b/specs/simple-serialize.md
index b609aa100..b888ca76f 100644
--- a/specs/simple-serialize.md
+++ b/specs/simple-serialize.md
@@ -390,7 +390,7 @@ Return the hash of the serialization of the value.
 
 #### List/Vectors
 
-First, we define some helpers and then the Merkle tree function.
+First, we define the Merkle tree function.
 
 ```python
 # Merkle tree hash of a list of homogenous, non-empty items
@@ -406,7 +406,10 @@ def merkle_hash(lst):
         items_per_chunk = SSZ_CHUNK_SIZE // len(lst[0])
 
         # Build a list of chunks based on the number of items in the chunk
-        chunkz = [b''.join(lst[i:i+items_per_chunk]) for i in range(0, len(lst), items_per_chunk)]
+        chunkz = [
+            zpad(b''.join(lst[i:i + items_per_chunk]), SSZ_CHUNK_SIZE) 
+            for i in range(0, len(lst), items_per_chunk)
+        ]
     else:
         # Leave large items alone
         chunkz = lst