Contains the correctly calibrated springs you need to lower pull weight and improve trigger pull quality of your Glock pistol without complicated gunsmithing or permanent alterations. Installing this kit will not disable or diminish the effectiveness of the well-proven Glock Safety System. Designed specifically to meet the needs of competitive shooters; this alteration is not recommended for duty pistols. Mfg: Wolff SPECS: Steel. Includes one (1) each of the following springs: 4lb. reduced power striker spring, reduced power safety block spring, and extra power trigger spring. Fits all models and calibers of Glock pistols.