Improved Ultra DI resin bags with an intuitive color-coded system and a KeyLock feature for proper installation. This system holds 1 DI Resin bag at a time (with the green KeyLock on top and red on the bottom). Setting a new standard in deionizing filter technology for pure water cleaning. The FloWater Technology 2.0 in every Ultra resin pack ensures and efficient flow of water through the whole tank, optimizing the resin saturation. Every Ultra resin pack contains a pre-portioned amount of Unger premium ion-exchange resin with a new formula, perfected for glass cleaning.