This is a Brand New 2 Pack Aimpoint 9000SC Red Dot Sight Double Battery Holder Assembly. Although only one is required, we're tossing in an extra. These are also for the 9000SC. The old bushing currently on your Red Dot has been replaced with a battery extender assembly, which lets you install two batteries and thus gives your Red Dot more battery life. These will fit on the M3, as well. NOTE: These do not fit the original Aimpoint CompM XD, which was from 1997 and discontinued in 2000.