These barrel grips are used with the Comp chassis for a very light build. The grips are made from smooth-skin NPVC foam that is designed for exercise equipment grips. They are very comfortable and tough. Standard length is 6.5″ but I’ll custom cut to any length on request. The grips are 0.875″ ID so they are easy to install and adjust on 10/22 bull barrels, but stay put when shooting. A little isopropyl alcohol applied to the inside of the grip helps installation but is not necessary. Outside diameter on the standard grip is 1.375″ and on the chubby grip it is 1.775″.