CNC aluminum spring plug and guide rod upgrades your Tokyo Marui Hi-CAPA 5.1. Lightweight design reduces recoil and improves gas efficiency, giving you more shots per magazine. Reduced friction improves efficiency and performance, making your Hi-CAPA more reliable and accurate. Delrin insert in recoil spring plug reduces friction, making movement smoother. Compatible with all Tokyo Marui Hi-CAPA 5.1 and Gold Match models.