Check-Mate Industries is an ISO 9001:2000 certified manufacturer of high quality products. Each replacement magazine is inspected at the factory to ensure reliable performance in your firearm. These magazines will stand up to hard use in competition or on duty. Check-Mates' unwavering fixation with creating the finest magazine has lead to an unparalleled number of innovative features each one more ground breaking then the next. Check-Mate's magazines are made from the highest quality American milled stainless and high carbon steel. Every tube is through-hardened for exceptional strength and durability. Each Tube is polished inside and out to eliminate drag and proprietary welding techniques insure solid welds that won't break. Check-Mates high-performance springs offer high quality, outstanding reliability, and exceptional spring endurance. Every detail from the feed lip to floor plate is driven by the same concern for excellence.