This Battle Arms Development 6 Position Carbine Buffer Tube is constructed from 7075-T6 aircraft-grade aluminum has a hard black anodized finish, will fit all standard AR15/M16/M4 lower receivers, and is made in the USA. Battle Arms Development, Inc. (B.A.D. Inc.) is a design, research, and development firm incorporated in 2009 with a focus on small arms design including firearm components, tools, gauges, accessories, and complete weapon systems. RSR - MPIMAG566BLK