If you have a Ruger 10/22 with a drilled and tapped receiver, then you absolutely must have the UTG Pro Ruger 10/22 Picatinny Rail Mount. The contoured bottom gives it a perfect fit and it has a low profile design with u-cut for weight reduction. It is precision machined from aircraft grade aluminum with a matt black hard-coat anodized finish. It has a 4.67" length with 11 Picatinny rail slots for Dot Sights, Rear Sights, and flexible positioning of magnified optics for proper eye relief adjustment. Includes assembly screws and tools for simple and easy installation.