In the field... seconds matter. If your optic sits too low; your head drops, your eyes shift, your posture breaks and that costs time. The Lerna and Hydra are the first optic mounts that offer a 2.91” Optic Centerline for faster target ID, regardless of gear/ equipment obstructions. The difference is immediate. Less strain on your neck, faster target transitions, and better awareness when it counts. Add UNITY™ Tactical’s revolutionary Flip-to-Center technology, the 2.91 FTC (Flip-to-Center) to bring any magnifier to the 2.91 height to pair with the GBRS Group Hydra Mounting Systems.