XD-M Compact 13-Round Extended Magazine, with magazine sleeve 2, for use with backstrap size #2 - .45ACP This magazine is intended for use in compact sized XD-M and XD-M Elite .45ACP models, effectively converting the grip from compact to full size. The included magazine sleeve, as noted, aligns with the installed backstrap already on the pistol creating a seamless transition from compact to full size and allowing the user extra capacity in a compact platform. To ensure proper fitment, magazine with sleeve #2 needs to be used with backstrap #2.