diff --git a/gemma/gm/nn/_modules.py b/gemma/gm/nn/_modules.py
index b1bbc789..4c7648ce 100644
--- a/gemma/gm/nn/_modules.py
+++ b/gemma/gm/nn/_modules.py
@@ -269,7 +269,7 @@ def __call__(
       attn_mask *= sliding_mask
     elif self.attn_type != AttentionType.GLOBAL:
       raise ValueError(
-          'Attn_type must be either AttentionType.GLOBAL or'
+          'Attn_type must be either AttentionType.LOCAL_SLIDING or'
           f' AttentionType.GLOBAL not {self.attn_type}'
       )