Be prepared for whatever may come your way by picking yourself up a spare magazine for your compatible Glock 17 from UMAREX. Constructed fully from metal, this high quality magazine is realistically weighted and can withstand hard impacts during rough use. A high tension internal spring smoothly feeds the .177 caliber BBs from the magazine into the firing chamber of the G17. A single 12g Co2 cartridge powers this magazine, which is housed directly inside the magazine. Stock up on everything you need for those extended training sessions, and get yourself a spare 18 round magazine today.