The Shield Arms Glock 43X/48 Mag Catch in Gold is made from steel and optimized to work specifically with the Shield Arms S15 magazine. While it is compatible with plastic OEM magazines, prolonged use may lead to increased wear on plastic components, and OEM magazines may not drop free. Shield Arms does not recommend using their steel mag catch with plastic OEM mags, advising users to pair steel with steel or plastic with plastic for best performance. Additionally, if you have a first-generation aluminum mag catch, it may not function with generation 2 S15 magazines, and upgrading to a steel catch is recommended for improved compatibility.