Rugged and precise, the Weaver Top-Mount Single Scope Base can be used with a second one based on your firearm's fitment (not included) to complete your custom setup. This Weaver-style scope ring base is constructed of machined aluminum. Custom-hardened fastening screws included. For use with a second one based on firearm fitment Machined aluminum base Includes custom-hardened fastening screwsHow to order your scope base: Find your rifle on the rifle model chart below Order both item numbers (front and rear) that fit your rifle For replacements on 2-piece bases: make sure to order the correct part (front or rear) to replace the part you are missing.View the Rifle Model Chart