Specifications Construction: Polymer Compatibility: Most 20Mm Rail Integration Systems Color: Black Package Includes: Flip-Up Rear Sight Features Spring Loaded Quick Pop-Up System High Quality Polymer Construction Locks Down For Sight/Scope Integration Compatible With Most 20Mm Rails (Picatinny & Weaver) Durable Long Lasting Construction Easy Target Acquisition Design Easy Lock Up/Down Position Textured Ergonomic No Slip Grip