The Vortex Precision Matched 30mm Rings are machined with certified USA 7075 T6 billet aluminum and held to an extremely tight tolerance of .0005 inches using a precision Computer Numeric Controlled (CNC) mill. These Vortex rings are then serialized, vibratory tumbled, bead blasted and finished with a Type III hard coat anodize to provide high-end rings for your next rifle set-up. When you want a very accurate set of 30mm rings, the Vortex Precision Matched 30mm rings are that option. They are lightweight at only 2 ounces yet rugged and have an anti-snag design. They are robust, grade 8 fasteners that are 100% made in the USA and guaranteed for life with the Vortex Lifetime Warranty.