^I just ordered one last week, just got it today.
It fits just fine, AFTER, you do some minor grinding...
Have a dremel and a decent grinder-bit ready, the plunger will not index with the notches as they come out of the box. So depending on your AK, regular length, or the carbine-length; you will need to mill-out the index slot for the plunger a bit.
It really was easy, I did it freehand and it turned out great. Took about 10-15 min and I was being careful, taking my time.
I didn't measure or anything, got a few errands to run, then off to work later. But if I remember I'll post pics later and measure the actual difference... I wanna say this muzzle-brake is at least an inch shorter than the standard '74 style' one, probably 1.5" ...
Have yet to shoot it (obviously), but thus far I'm happy with the purchase. If you are looking for a good brake to shorten the OAL, I would buy this again.