SIG SAUER Alloy Grips are precision machined from a solid billet of aircraft grade 6061-T6 Aluminum and treated with a black anodize finish. Manufactured by SIG SAUER to high tolerances, these grips provide excellent ergonomics and will handle the most extreme conditions. Due to the strength of the material, these grips are generally thinner than the standard polymer grips. Machined checkering provides a firm purchase in wet or slippery conditions. Please note: when changing from wood to polymer or wood to aluminum grips, you need to purchase screw sets.