Quick Fist clamp. Used to mount tools or equipment on a vehicle. For work and emergency vehicles, off-road trucks, military equipment, ATV's and boats. The 3 inches nozzle Quick Fist clamp holds objects from 2-3/4-inches to 3-1/4-inches (70 millimeters to 83 millimeters) in diameter. Each clamp supports a safe working load of 50 pounds or 23 Kilos. Mounts easily with one 1/4-inches (6-millimeters) bolt or screw (not included). Mounting area: 4-1/2-inches x 1-1/4-inches (113 millimeters x 32 millimeters)