The Primary Arms Deluxe Extended AR-15 Scope Mount is ideal for shooting a variable power optic in the "nose to charging handle" position on M4, AR-15, and similar "flat-top" 1913 Picatinny mounting platforms. It's a great option for 1-4x and 1-6x scopes with 30mm tubes. Aluminum construction, durable matt black anodized finish. 2.28 inches of clearance between the rings. Places the center of your 30mm tube scope 1.5 inches above the rail.Features:For optics with 30mm or 1" tube diametersMachined from aluminumMatte black anodized