Leveraging UNITY Tactical's revolutionary Flip-to-Center technology, the 2.91 FTC (Flip-to-Center) elevates any magnifier to the 2.91 height for compatibility with the GBRS Group Hydra Mounting Systems. The 2.91 FTC Mount uses a straightforward force-to-overcome mechanism and tucks the magnifier below the optical sight plane, fully within the weapon's receiver footprint when not in use. This design removes the need for flip-to-side placement seen in legacy products, offering all the benefits of magnification when needed, with no obstruction of sight pictures when stowed.Features :"Height: 2.91" to Optic Center Line"Interface: 30mm RingMechanism: Force-to-OvercomeRail Mount: QD leverConstructed of 7075 T6 AluminumWeight: 4.9ozType III Hardcoat Anodized