PDI W Hold Hop Up Chamber Packing for VSR-10. Fits original hop up chambers (not PDI upgrade). This hop up will also work in most Tokyo Marui gas blowback guns. Fits MP7, Detonics, Sig P226, G series, 1911, HiCapa (including xtreme), MEU, FN57, G18c, Warrior series, PX4, and more! Will not fit in the Desert Eagle. Will work in KJW clones. High quality, made in Japan.