Oh, those dreaded water spots. Wash your car, rinse it, and now you have to polish out all the spots. No more. The 24" tall, 7 1/4" diameter tank comes filled with 13 lbs. of our exclusive ion-exchange resins that remove minerals from the water through a process that binds them to the resin. Because the majority of the impurities are dissolved, deionization produces highly purified water, so no more spots! The two valves control the water flow through the filter. This allows you to bypass the filter when it is not needed to prolong the life of the resin. Add our Brass Quick Disconnect Set for faster, easy use. The life of the resin depends upon the amount of total dissolved solids (TDS) in your water. Want to know your TDS level? Check out Griot's easy-to-use TDS Meter. The replacement resin is safe, disposable, and easy to install.