ALPHA Series Folding Stock Shipped for rifle use, also compatible with Gear Head Works tailhook for arm brace use. Cosmetic arm brace plug sold separately to ensure back beam is smooth. Adjustable polymer cheek piece for comfortable use with all users Adjustable butt pad for increased usability with plate carriers or heavy gear. 5 position locking beam with textured button for quick changing Heavy-duty side-folding mechanism constructed from 4140 heat treated steel Compatible with firearms that include 1913 rail adaptor Full-length locking lug for maximum strength Solid positive lock up in both positions Steel clamp with large surfac Mfg: Midwest Industries