Caliber: 10/22 - Barrel: Standard / .920 Bull - Lenth of Pull: 10.375 - 14.375 - Length: 30.5 - 34.5 - Weight: 2.65 lbs - The ADTAC RM4 Stock is the most advanced and versatile stock available for the extremely popular Ruger 10/22 rifle. This innovative stock is loaded with more features than any other on the market. - The removable barrel insert provides a custom fit for both standard tapered barrels and .920 bull barrels. - Patented Stowaway accessory rail is concealed in the forend. When reversed the rail is available for a bi-pod or other accessories. - Get custom length-of-pull for proper fit and improved performance with the adjustable M4 type butt-stock equipped with ambidextrous storage compartments for two spare Ruger rotary magazines. (Magazines not included.) - The pistol grip is designed to fit the spring-loaded TacTRED monopod for increased stability (sold separately). TacTRED provides a quick stable single point rest on any surface and ensures maximum tripod-like stability when used with a front rail-mounted bipod or front rest.