RS BM-3 Picatinny Rail Accessory Mount BM-3 Picatinny Rail Accessory Mount for Century C39 and C39V2 pattern Kalashnikov Rifle allows nearly 360 degree placement and retention of cleaning rod in most applications RS BM-3 Picatinny Rail Accessory Mount is compatible with all rifles with barrels 0.66" outer diameter and requires no modifications to the host rifle 1.1 oz 6061-T6 MIL-A-8625 Type III Hard Anodize Black Allows retention of all stock heat shields, hand guards and cleaning rod Enables placement of any 1913 Picatinny accessory in nearly 360 degree position forward of the stock hand guards