Chrome-plated, solid brass eyewash unit easily installs on any existing sink or basin faucet as a permanent eye wash fountain with unlimited water supply in an emergency, unlike portable models. In operation, unit mounts behind the spout, where it remains out of the way for every day use. In an emergency, it frees both hands to hold eyes open to the flow of water. Delivering more than twice the required water flow, it does so at a reasonable height. It will function properly with as little as 15 lbs. of water pressure. It is restricted to reduce high water pressure to a velocity low enough not to be injurious to the user. No plumbing required. Two of the most common adapters are packed with the unit. Other adapters are available from manufacturer. Meets ANSI Standard #Z358.1-1998 for an eyewash unit. The addition of the Eliminator Valve allows water temperature to be pre-set at the faucet and remain on. You now have a dedicated eyewash station with only tepid water available. For sink use, the water flow is activated by the use of the push through plunger on the Eliminator Valve. The faucet handles will no loinger be used after the water temperature is set. Push the plunger to the opposite side for water flow.