2-1/2 in. (63.5 mm) Plastic Cap & Chain protects hose angle valves, hydrants, or other 2-1/2 in. NST-threaded male outlets from dirt, dust, and debris. Made from durable red plastic, this 2-1/2 in. cap and chain comes standard with National Standard Thread (NST) threads, a water-tight gasket, and a chain.
The included chain connects the 2-1/2 in. (63.5 mm) NST Cap to the valve or hydrant to avoid loss while uncovered.
I own a 1940 Ford/Buffalo panel truck pumper. I bought the caps to protect the male threads while handling the lightweight suction hose I just bought. The caps fit perfectly and look good on the hose. The rack is below the roof and the front of the hose is above the driver's head.