Each Heckler & Koch MP5 magazine offered by Keepshooting.com is designed to hold and feed 40 rounds of 9x19mm Parabellum ammunition to your MP5. Alternately, these magazines are compatible with several other MP5-patterned firearms, including the Bobcat BW5, the Special Weapons SW5 and the Vector Arms V94. And though they are patterned after the original Heckler & Koch MP5 factory magazines, they are available for a fraction of the price. Guaranteed to fit and function in your MP5, these magazines are a must-have accessory for any MP5 owner.