Centennial Defense Systems Competition Trigger Spring Kit for Gen 1-4 Glock. Each spring is made in specialized factories of premium silicon wire. Kit Includes: 4lb Striker Spring 6lb Trigger Spring Reduced Power Firing Pin Safety Spring Note: This kit is designed for competition not duty or carry use. All Centennial Defense Systems products are designed manufactured finished and assembled in the USA. Specifications for Centennial Defense Systems Competition Trigger Spring Kit: Manufacturer: Centennial Defense Systems Color: Stainless Steel Fabric/Material: Stainless Steel Gun Make: Glock Gun Model: Universal Features of Centennial Defense Systems Competition Trigger Spring Kit 4lb stirker spring 6lb trigger spring Reduced power firing pin safety spring Package Contents: Centennial Defense Systems Competition Trigger Spring Kit What firearm models does the manufacturer say Centennial Defense Systems Competition Trigger Spring Kit is compatible with? The manufacturer suggests that Centennial Defense Systems Competition Trigger Spring Kit is compatible with UniversalCentennial Defense Systems 30172: Competition Trigger Spring Kit for Gen 1-4 Glock