Water-saving 1.0 gpf (3.8 lpf) flush valve uses 22% less water than 1.28 gpf (4.8 lpf) flush valves;Activation distance is factory-set;Chloramine and chlorine resistance on all rubber components exposed to waterway;Engineered for optimal performance with Kohler commercial fixtures;125-micron filter protects internal components;High back pressure vacuum breaker;Locking stop cap provides protection against vandalism;No external flush volume adjustment ensures water conservation;24-hour automatic sentinel flush keeps trapway fresh;Mechanical override enables flushometer to be used manually even during a power outage;Powered by 1.5V AA lithium batteries