Looking for Riflescope Mounts and Bases? Ruger Weaver-Style Scope Base Adapter for Mark I/II/III and 22/45 Black delivers great quality for a great price. All of the features you need for a price you want from Ruger. Don"t look further for Riflescope Mounts and Bases. Ruger Weaver-Style Scope Base Adapter for Mark I/II/III and 22/45 Black has everything you"ve been looking for.