The Cylinder & Slide Disconnector has been approved by the U.S. Marine Corp and is manufactured to the exact same specifications and tolerances and use the same manufacturing materials as the original parts. This replacement part has been cut from special alloy plate steel. This steel has been heat treated to 44-46 Rockwell C for unlimited life expectancy. Suitable for all applications, these parts have been expressly designed for the tactical pistol. Parts require fitting by a qualified gunsmith.