Made in USA, not China. Compatible with all 1911s built to US standards, for all full size grip screw bushings and slim grip screw bushings and grips not less than 0.188" (3/16") thick. Made of stainless steel with a black oxide finish. The included O-rings go around the grip screw, preventing the screw from loosening on recoil. Challis Grips has a reputation for outstanding quality. Look closely at the photos above for the crisp details and to see the screws in a variety of grip and gun combinations. All of the grips in the photos (except the black ones) were made by Challis Grips. For optimal performance use with Challis 1911 Hex Drive Grip Bushings, a patented system that prevents the grips from shifting during discharge, providing the most secure grip mounting available for 1911 handguns. Not compatible with foreign made guns that don't use the .150-50 thread pitch specified in the ordnance drawings for 1911 handguns. Challis Grips is a small family business focused on exceptional quality products for 1911 handguns. We got started making amazing custom grips to order. On Amazon we offer our patented hex drive grip bushing system, the best bushing removal tool available anywhere and a line of beautiful grip screws. Our passion for excellence extends to our customer service...if you ever have a problem with any of our products, we will make things right as quickly as possible. Search for Challis Grips to see all of our products.