Tactical Solutions 1in Pac-Lite Compensator Matte Black. The Pac-Lite Compensators feature 360 ports to help reduce muzzle rise while maintaining a clean classy look that matches the contour of any 1 target barrel. The compensators easily thread on to 1/2 x 28 threaded-end barrels. Specifications for Tactical Solutions 1in Pac-Lite Compensator: Manufacturer: Tactical Solutions Fabric/Material: Aluminum Threads per Inch: 1/2x28 Gun Make: Ruger Gun Model: Ruger Mark IV 22/45 Ruger Mark IV Ruger Mark I Ruger 22/45 Ruger Mark III Ruger Mark II Length: 0.92 in Weight: 1.5 oz Condition: New Projectile Caliber: .22 Caliber Diameter: 1 in Features of Tactical Solutions 1in Pac-Lite Compensator Reduce Muzzle Rise: unique design will improve muzzle control Lightweight: Virtually no weight added with lightweight aircraft aluminum construction Quick and Easy to Install: Simply thread onto your threaded-end barrel Package Contents: Tactical Solutions 1in Pac-Lite Compensator What firearm models does the manufacturer say Tactical Solutions 1in Pac-Lite Compensator is compatible with? The manufacturer suggests that Tactical Solutions 1in Pac-Lite Compensator is compatible with Ruger Mark II Ruger Mark III Ruger 22/45 Ruger Mark I Ruger Mark IV Ruger Mark IV 22/45Tactical Solutions PLCMP-MB: 1in Pac-Lite Compensator Matte Black