QMP502HNDL is a 1/4", 3/8", and 1/2" Compression Diverter Valve that connects to your kitchen faucet. This diverter valve allows you to switch between the water from your faucet and filtered water from the unit. The tubing attaches snuggly to the compression connection and diverts the water to the filtration unit when you turn the handle. This diverter valve combines the best features of QMP502 and QMP502PD making it perfect for high AND low pressure applications. Simply turn the handle in the opposite direction to return to unfiltered water. NOTE: 1/4", 3/8", and 1/2" OPTIONS REFERS TO OUTER DIAMTER OF THE TUBE NOT THE SIZE OF THE BARBSPECIFICATIONS:1/4" Barb size : 0.2245 inches3/8" Barb size : 0.2850 inches1/2" Barb size : 0.3910 inches