Centennial Defense Systems Trigger Assembly w/Stainless Steel Bar for Gen 1-4 Glock Blue Red except 10mm/.45ACP models. The polished steel results in less friction and a smoother trigger pull. These assemblies are drop in units that do not require any fitting. Specifications for Centennial Defense Systems Trigger Assembly w/Stainless Steel Bar for Gen 1-4 Glock: Manufacturer: Centennial Defense Systems Fabric/Material: Stainless Steel Gun Make: Glock Gun Model: Universal Model Generation: 4 3 2 1 Package Contents: Centennial Defense Systems Trigger Assembly w/Stainless Steel Bar for Gen 1-4 Glock What firearm models does the manufacturer say Centennial Defense Systems Trigger Assembly w/Stainless Steel Bar for Gen 1-4 Glock is compatible with? The manufacturer suggests that Centennial Defense Systems Trigger Assembly w/Stainless Steel Bar for Gen 1-4 Glock is compatible with UniversalCentennial Defense Systems 20800: Trigger Assembly w/Stainless Steel Bar for Gen 1-4 Glock Blue Red except 10mm/.45ACP models