Strike Industries R.EX Riser Reflex Exoskleleton Weight: 2.58 oz Height (with spacer): .63″ Height (without spacer): .53″ Base: 6061-T6 AI, requires 5 rail sections to properly mount Total length: 2.09″ Finish: Anodized (Black) Features: Low profile riser, Lightweight co-witness height, Co-witness with A2 or Sidewinder sight, 3 picatinny slot sections Note: Medium Strength Loctite Recommended (Included). Note: Uses a proprietary picatinny rail design. Will work for most mil-spec 1913 style rail attachments however.