Unity Tactical FAST Red Dot Sight Mounts Black. 26" optical centerline from the rail. It comes standard with a two cross bolt rail clamp" but is compatible with the FAST QD (Quick Detach) Lever. It can be paired with any FAST FTC (Flip-to-Center) magnifier mount. FAST is a series of optic mounting solutions that provide end users with a quicker sight picture than standard height mounts. FAST mounts create a 2.26" optical centerline from the rail" which allows for more rapid visual processing of the battlefield by ensuring an ergonomically correct heads-up posture. Further" they provide faster and easier dot/reticle acquisition while wearing night vision goggles" protective masks" plate carriers" and other gear. Specifications for Unity Tactical FAST Red Dot Sight Mounts: Manufacturer: Unity Tactical Finish: Anodized Condition: New Case Finish: Anodized Blade Finish: Anodized Gun Rail: Picatinny Handle Finish: Anodized Features of Unity Tactical FAST: 7075-T6 Aluminum Construction Package Contents: Unity Tactical FAST Red Dot Sight Mounts Unity Tactical FST-RLB: FAST Red Dot Sight Mounts Black