H&K USP CO2 AIRSOFT – BLACK. The HK USP CO2 Airsoft Pistol is the competitor’s choice for fast, accurate CO2 action during airsoft competitions. UMAREX holds the worldwide exclusive HK-trademark and exterior design copy license for use with this UMAREX product, granted by HK, Inc., U.S.A. Licensed Trademark of Heckler & Koch GmbH