Our steel mag catch is optimized to work with the Shield Arms S15 magazine. While it remains compatible with plastic OEM magazines, it can cause increased wear on plastic mags with prolonged use, and OEM mags may not drop free. We do not recommend using our steel mag catch with plastic OEM mags. We recommend steel on steel or plastic on plastic.
If you have a first generation aluminum mag catch, it may not work with gen 2 S15 mags. We recommend upgrading to one of our steel catch offerings.