A complete offset optic mount requires both a base and one optic plate. This product listing is only for purchasing spare plates. Tall height (1.9" to 2.2" scope mounts): Plate 5: Aimpoint Micro T1/T2/H1/H2, SIG Romeo 4, 5 (not 5X), Holosun HS403 (not A), HS503, HS515, HS530, Vortex Crossfire Do not exceed 20 inch lbs of torque on the screws that attach the optic to the plate. Made in the USA. Each plate is CNC machined from 6061-T6 aluminum and MIL-A-8625 Type III hard coat anodized. Please refer to the instructions for torque values and mount configuration. All plates include new screws (where needed) which we highly recommend using over the OEM screws. The Leupold DPP plate 4 and 10 include extra long screws to attach the optic to the plate that require a 2.5mm Allen key.