Installation of these parts kits requires disassembly of your firearm beyond a field-stripped condition. Improper installation may result in malfunction, serious injury, or death. SIG SAUER requires that only certified SIG SAUER armorers install these parts kits. Any damage caused by the incorrect installation of these parts kits is not covered by your firearms warranty, and SIG SAUER will charge for any needed repairs to a firearm damaged by improper use or installation of these parts kits. Includes: Blue flat trigger, Blue slide catch lever, Blue take-down lever, Blue magazine catch, Blue catch lever spring, Magazine catch spring, Magazine catch stop, Trigger pin, Trigger bar spring