The B5 Systems CAR-15 stock is a retro-styled fixed buttstock for AR-platform rifles. It mounts on a standard mil-spec receiver extension and does not collapse, so your cheek weld stays rigid and consistent shot to shot. It is a good fit for retro builds and for shooters who want a fixed stock without the length of a full A2. The mil-spec polymer body carries B5's checkering and a knurled anti-slip butt plate that holds its place in the shoulder. Multiple fixed sling points give you options for how the rifle rides, and an egress channel is molded into the stock. Features: Fixed (non-collapsible) CAR-15-style buttstock Mil-spec polymer construction Multiple fixed sling attachment points Knurled anti-slip butt plate with checkering Egress channel Roughly 4.2 oz; about 6.21 inches long; black finish Fits standard mil-spec receiver extensions only. It does not fit commercial-diameter buffer tubes. Confirm your receiver extension is mil-spec before ordering, and check that the stock seats fully and does not wobble after installation.