Zip AquaSense_ Touch-free tap range incorporates simple and modern design, with the latest electronic functionality delivering maximum hygiene and efficiency with integrated flow control achieving a 6 Star WELS rating for maximum water savings, the tap also features an automatic purge function, sensor range adjustment, wave on/wave off function, Anti-Vandal and Lock Out functions and a Chlorination function._Surgeon models have a 20 second run-on after use.