Ruger Length-of-Pull Spacer Kit Ruger American Rifle Gen 2 Black. The correct length-of-pull improves the rifle's comfort and feel and improve accuracy by making shoulder placement and sight acquisition faster and more consistent. The rifle ships with a 13.75in length-of-pull spacer installed. The spacers in this kit allow additional adjustment to the rifle's LOP. The spacers included in the kit provide a 12.75in or 13.25in LOP when installed. Change spacers by loosening the recoil pad assembly and installing the appropriate spacer. Only one spacer can be utilized at a time; spacers cannot be stacked for extra-long LOP. Changing spacers is quick and easy using a 3/16'' hex wrench and 7/16'' socket or wrench. A 1/8in hex wrench or similar tool is required to loosen the rear swivel stud (not included). Specifications for Ruger Length-of-Pull Spacer Kit: Manufacturer: Ruger Color: Black Gun Make: Ruger Gun Model: Ruger American Rifle Gen 2 Package Contents: Ruger Length-of-Pull Spacer Kit What firearm models does the manufacturer say Ruger Length-of-Pull Spacer Kit is compatible with? The manufacturer says that Ruger Length-of-Pull Spacer Kit is compatible with Ruger American Rifle Gen 2Ruger 90747: Length-of-Pull Spacer Kit Ruger American Rifle Gen 2 Black