|On a 26" barrel, it does stick out a little - not enough to keep it from functioning, but enough to make it give it an "underbite." Cosmetically, it looks better on a 28" barrel.
It is 9+1 and you likely will have to grind tabs. Pain to do, but true of all extensions. Works better with a good steel follower than the cheap plastic ones in most 870s.
Be prepared for a HEAVY gun when loaded - but it is a TON of fun to go shooting with.|