Polymer 27 Round, .45 ACP Magazine, Extended Magazine For Glock .45 acp, 21 and 30, double stacked magazine well only. These high capacity magazines have proven to be reliable in our tests with semi auto Glocks as well as Select fire Glocks. They are polymer high capacity magazines with steel feed lip inserts for easy feeding. Fits all .45 Cal Glock pistols. **Does not fit Glock 36.