These Unger quick change HydroPower Resin Bag fit the HydroPower™ Ultra PureWater Window Washing tanks and kits. These HydroPower DI filters are made from a water-permeable material and contain a pre-proportioned amount of Unger High Capacity Premium Grade Virgin Mixed Bed resin to produce pure water in the fastest and most efficient way. These bags allow users to speed up the resin change process by up to 10 times by simply removing the bag with expired resin and insert a new one. They are color-coded and feature a KeyLock system to assist with proper DI resin installation.