Complete assembly, ready-to-install Advanced steel hinge design locks in both folded and extended positions Pull-through design offering quick deployment Rigid polymer substrate with flexible arm cuff US veteran designed and proudly made in the USA A low-profile, left side-folding triangle design compatible with all platforms utilizing an M1913 (Picatinny) interface at the rear of the receiver. The TF1913 is a complete assembly offering pull-through opening and a solid lock-up when extended.