The Schmid Tool Gun Nuts line of AR-15 Parts was crafted by Schmid Tools, a company that has been producing fire control groups and lower parts kits for military contracts since 1980. Schmid Tool knows exactly what goes into making every part perfect. The Schmid Tools GI line is a traditional government issued semi auto mil equivalent Phosphate trigger and hammer. Includes:TriggerHammerDisconnectHammer SpringTrigger SpringDisconnect SpringHammer PinTrigger Pin