This 30 MOA scope base is designed for long-distance shooting with the Ruger Precision Rimfire. The rail is engineered to fit the factory scope-mount holes on the receiver; MIL-STD Picatinny slot-and-rail spacing accommodates Picatinny or Weaver scope rings. One-piece design, precisely machined from billet aluminum. Measures 5.25 inches long with a hardcoat anodized finish; includes four Torx mounting screws and a T-10 wrench. Made in the USA. Genuine Ruger factory accessory.