This flat trigger is designed to fit in the frame very tightly and reduces side-to-side wobble found in the factory trigger. The Pre- and Over-travel adjustments are highly improved over the factory trigger and allows for shorter reset and full adjustability. By replacing the included factory trigger plunger spring with our #19 lightened trigger plunger spring, you will reduce the pressure form the trigger plunger onto the trigger bar. The trigger pin hole is .102" and allows for the Flat Trigger to precise and freely move with your factory roll pin. The trigger comes complete with steel trigger lever, #17 trigger return spring, #19 lightened trigger plunger spring, pre- a Mfg: Henning Group