San Raphael Comfort Height 1-Piece 1.0 GPF Single Flush Elongated Toilet in Thunder Grey, Seat IncludedPowered by a Sloan FLUSHMATE pressure vessel, the Thunder Grey San Raphael 1 piece high efficiency toilet from KOHLER supplies premium flushing power using significantly less water than standard commodes. Each 1. 0 Gal. flush represents a 37. 5% reduction in water use compared with ultra low flush 1. 6 GPF toilets that have been commonly installed in bathrooms since the mid 1990s. Combining form with function, the low profile of the San Raphael