771 series folding stock includes 77121. The original JCS X7 COMBAT folding stock by the inventor, Blackpoint! Features the new "771" series hinge design. The 771 hinge allows users to change the open position of the folding stock from straight to more than 10 degrees angle offset. This allows you to sight your target with an upright natural posture. With the RVA, you will optimize your air usage and increase performance. Only weighing about a pound, this stock is precision machined from aircraft grade aluminum bar stock. Black anodized.