Selectronic Battery-Powered Dual Flush Valve for 1-1/2" Top Spud ToiletsSelectronic electronic flush valves are engineered to meet the demands of high use spaces with a design that offers water saving operation, easy installation, and lost cost maintenance. This battery powered Selectronic dual flush is designed for use with 1 1 2" top spud flushometer toilets. Delivers a light flush (1. 1 gpf: 30% water savings) if user is in detection zone for 60 seconds or less and a standard flush (1. 6 gpf) if user is in detection