This mechanical sleeve wraps around a burst or leaking section of fire hose to temporarily stop water loss without shutting down the pump. It consists of two hinged halves lined with rubber that lock tightly over the damaged area. Crews also use them to connect two hoses with mismatched or damaged couplings.
Heard on the job
Grab the hose jacket from the compartment, we've a pinhole leak on the supply line and I don't want to shut down the hydrant.