diff --git a/i2p2www/pages/site/docs/spec/tunnel-message.html b/i2p2www/pages/site/docs/spec/tunnel-message.html
index 5dec4c6b..05c00c69 100644
--- a/i2p2www/pages/site/docs/spec/tunnel-message.html
+++ b/i2p2www/pages/site/docs/spec/tunnel-message.html
@@ -277,7 +277,9 @@ frag ::
 
 Message_ID ::
        4 bytes
-       the same ID specified in the first fragment for this message ID
+       Identifies the fragment sequence that this fragment belongs to.
+       This will match the message ID of an initial fragment (a fragment
+       with flag bit 7 set to 0 and flag bit 3 set to 1).
 
 size ::
        2 bytes