65 sportster cylinder head, which ones right?

[bkrfrmhell]

Ordered a new head from K&B, part number 11-5801, recieved a 5816. Head is about half as deep and does not have an oring groove like the old one. Whats is going on? Looks like it will fit. I would prefer to have one thats the same as the old one. Is a direct match still available?

[MECOA]

The deep fins and the oring groove is the early version. The engines ran too cool so the fin height was reduced. The o-ring head seal didn't work as well as the metal to metal. We don't have any of the early heads in stock but be assured the new one works better. The changes would not have been made if it were not the case.