diff --git a/specs/deneb/p2p-interface.md b/specs/deneb/p2p-interface.md
index b11e61ef6..531161b4e 100644
--- a/specs/deneb/p2p-interface.md
+++ b/specs/deneb/p2p-interface.md
@@ -70,7 +70,7 @@ class SignedBlobSidecar(Container):
 ```python
 class BlobIdentifier(Container):
     block_root: Root
-    index: uint64
+    index: BlobIndex
 ```
 
 ## The gossip domain: gossipsub