ChlorMaker IL Hot Tub and Spa Inline Saltwater System Chlorine Generator, Chlorinator is installed in with the existing plumbing Spa and Hot Tub Chlorine Generator, Around-The-Clock Chlorine Production 10 Built in Power levels, no external timers needed! Self Cleaning Reverse Polarity Technology, Lowers spa and hot tub maintenance Dealer installation recommended, integration with existing equipment is required No more skin irritations and itchy red eyes, enjoy your spa LONGER!