This is the standard QD mount for the Trijicon MRO™ (Miniature Rifle Optic) allowing 1/3 Co-witness with the Iron Sights on M4 Carbine and AR-15 Flattops. Like all LaRue mounts, they are precision-machined out of bar-stock aluminum and matte black anodized to provide a durable non-reflective surface finish. The locking LaRue Speed Lever provides outstanding return to zero; the optic can be removed, and replaced, without loss of zero. Guaranteed.