Weaver Top Mount Aluminum Bases Experience unmatched precision and reliability with the Weaver Top Mount Aluminum Bases. Machined to exacting tolerances, these bases deliver a custom fit and ensure maximum strength for securing your riflescope rings. Key Features: Custom Precision Fit: Crafted with tight machining tolerances to provide a seamless fit on your firearm. Rock-Solid Cross-Lock Design: Features Weaver's trusted cross-lock design for secure compatibility with a variety of riflescope rings. Proudly Made in the USA: Precision-manufactured to deliver the highest quality and reliability. Weaver Recommended Torque Specs 6-48 Screws: 15 in lbs 8-40 Screws: 18 in lbs Note: Product is a one-piece base; some firearm types may require the purchase of both a front and a rear base. Please refer to the Fit Finder or Weaver Base Chart for more information. Instruction Manual