Step 5 · Remove Old Supply Line and Purchase Replacement
It is most efficient to replace the entire supply line. Disconnect the other end of the line from the faucet's threaded tailpiece. This nut can be difficult to reach; a basin wrench is the ideal tool, but you may be able to use an adjustable wrench or pliers. Once removed, take the old supply line to a hardware store. Purchase a new braided stainless steel supply line of the exact same length and with the same size connection nuts.