New item for upgrading these pistols from X-Fire/PDI... "For Tokyo Marui M1911A1 ,MEU & DETONICS.45. Made of CS(Carbon Steel), all CNC machined and black oxide finish.　It looks tough and wild. We made account of reproducing mechanical section and durability .(If you want to keep it clean, please do maintenance to prevent from it rusting). For using Custom Hammer the normal sear is made of zinc die-cast. It is undurable material. The cycle of shooting change of sear's shape. PDI's sear is made of CS, so it enhances durability."