Strike Industries Enhanced Magazine Plate for Glock 17/22 Magazines, +6 for 9MM and +5 for 40S&W, Black SI-EMP-G940 The Strike Industries Extended Magazine Plate For GLOCK G17 9MM / G22 .40CAL was designed to provide smoother magazine reloading through a slow drag / no snag design while maintaining maximum magazine capacity with any OEM GLOCK magazine. The Extended Magazine Plate provides an additional 6 rounds to any G17 GLOCK magazine in addition to adding plus 5 to any G22 .40 cal magazine.