Ruger Weaver-Style Scope Base Adapter for Mark I II III and 22-45 Black. OpticsPlanet is an Authorized US Distributor for Ruger Riflescope Mounts Rings & Bases. Anodized aluminum. Specifications for Ruger Weaver-Style Scope Base Adapter for Mark I/II/III and 22/45 Black 90228: Manufacturer: Ruger Color: Black Fabric/Material: Aluminum Gun Model: Ruger Mark I Ruger Mark III Ruger Mark II Additional Features: Scope Base Adapter Package Contents: Ruger 90228 Weaver-Style Scope Base Adapter for Ruger Mark I/II/III and 22/45 Black We offer the complete line of Ruger Riflescope Mounts Rings & Bases. For our complete selection of products by Ruger on sale please visit our Ruger page. For more Rifle Scopes & Accessories please visit our Rifle Scopes & Accessories store section. Ruger Weaver-Style Scope Base Adapter for Mark I/II/III and 22/45 Black