The HK VP9 blowback slide .177 caliber BB air pistol is another must-have Umarex air pistol from one of the most renowned names in the arms world. With the HK VP9 air pistol, you get the same ergonomics, function, and fit as the original that you can use in your garage. Getting into the action is easy with the drop free mag that houses 18 .177 caliber BBs along with the 12 gram CO2 cartridge (CO2 NOT included). The Heckler & Koch VP9 is also equipped with a Picatinny style accessory rail located for easy mounting of lights, lasers, or other accessories. Licensed Trademark of Heckler & Koch GmbH.