Super easy push in Supply Valve for 1/4" tubing. This SV-6 fits copper pipe 3/8" & 1/2" in a diameter. Retract the needle of the valve first. You simply mount the valve on the cold water supply pipe. Just snug enough so that it will not turn or move. Turn the tee handle at the top of the valve all the way to the right. You will feel the handle bottom out. Now connect the RO unit inlet tube to the push in fitting. When you are ready to start up the system turn the tee handle all the way to the left . This is a self-piercing valve used to penetrate copper pipes.