H2Option Siphonic Dual Flush Toilet Tank with Push Button Actuator 1.28 GPFThis H2Optimum Siphonic dual flush toilet tank gives you the choice of either a full (1. 28 gpf) partial (0. 92 gpf) flush for maximum water savings. The tank is designed for use with the H2Option two piece toilets 2886. 218, 2887. 218, and 2889. 218. The tank is made of high gloss vitreous china and has a top mount, chrome push button actuator. Bowl and seat are not included and sold separately. 0. 92 gpf (partial flush) 1. 28 gpf (full flush)