The 1.70 inch bore height AUS Mount for 30mm diameter magnified optics, from Reptilia is driven by the request of an end user group, the AUS Mount is the culmination of a 2 year development program. Like Reptilia's DOT Mount line the AUS Mount attaches to any M1913 Picatinny rail via their anti-snag spring-loaded nitrided steel clamp and custom bolt mounting system which can be tightened with a T-25 Torx or a flat blade driver to sit flush with the body of the mount for a low-profile, streamline design. Also like Reptilia's DOT Mount line, the AUS mount is machined from a single piece of billet 7075-T6 aluminum and is finished with MIL-STD Type III, Class 2, hard anodize coating. The AUS is compatible with all of Reptilia's existing 30mm ROF line. Like all Reptilia products, the AUS Mount is 100% made in the USA and carries a full lifetime warranty against manufacturer defects.