The G&G Extended Crane Stock & Buffer Tube Kit comes with all the parts and accessories to mount to most airsoft AR style receivers. The kit includes the crane stock, buffer tube, sling mount plate, and mounting bolt assembly. The crane stock is constructed from durable, lightweight nylon polymer with a rubberized buttplate, and all othe rparts are made of metal. This stock is optimal for crane, nunchuck, or shorter stick style batteries. The crane stock is multi-positional and can be adjusted for length on the fly.