Our steel mag catch is optimized to work with the Shield Arms Z9 magazine. While it remains compatible with plastic OEM magazines it can cause increased wear on plastic mags with prolonged use. We recommend steel on steel or plastic on plastic. - Features - Steel mag catch several finish options - Ambidextrous - Chamfered textured button - Optimized for use Shield Arms Z9 magazines - Lower profile for concealed carry - Made in the USA - 100% lifetime warranty