actually, you won't get what you need as an mb- muzzle brake- it's an fh- flash hider- and at least get a picture as there are both styles out there- it's quite in vogue to replace the lugless with usgi or equiv- you'll also need the m6 bayonet, not the current m7/m9- it's a different locking mechanism-then go through the stickies on how to do the job- you'll need to get a hold of a castle nut wrench as well, once you break the welds by dremel or drill