Evolution Gun Works Officers Reverse Plug w/Solid End .825in Carbon Steel Blued Finish. 825"Hole Diameter:.257"Shoulder Length: .250"Spring Bore Depth: .725"Reverse Plugs from EGW are designed for easy installation and increased performance.Made from carbon steel (not lead alloy) to eliminate cracking the rounded shoulder is extended for added support with no exposed area where cracks can occur.A reverse plug is used in comp guns and bull barreled pistols where there is no bushing to retain the spring.The choice of "with" or "without" hole is an aesthetic preference and does not affect the functionality of the plug. This plug is for Officer's length slides only. Available in Carbon Steel only. Must be installed by a competent gunsmith. Specifications for Evolution Gun Works Officers Reverse Plug: Manufacturer: Evolution Gun Works Color: Black Finish: Blued Fabric/Material: Steel Gun Make: Colt Gun Model: Colt Officer's ACP Package Contents: Evolution Gun Works Officers Reverse Plug What firearm models does the manufacturer say Evolution Gun Works Officers Reverse Plug is compatible with? The manufacturer says that Evolution Gun Works Officers Reverse Plug is compatible with Colt Officer's ACPEvolution Gun Works 12051: Officers Reverse Plug w/ Solid End .825 in Carbon Steel Blued Finish