Starting with certified USA 7075 T6 billet aluminum, the Precision Matched are held to an extremely tight tolerance of .0005 using our precision Computer Numeric Controlled (CNC) mill. Kept in pairs throughout the manufacturing process, ensuring perfection from one set to another, these Vortex rings are then serialized, vibratory tumbled, hand-bead blasted and finished off with a Type III hard coat anodize.