Toto Auto Flush Kit For S7 & S7A Dual Flush Toilet - THU855TOTO Auto Flush Kit For S7 & S7A Washlet System Toilets Auto Flush Kit For The Washlet S7A And S7 Bidet Seats Only Compatible With Dual Flash Toto Washlet+ T40 Toilets Designed specifically for TOTO WASHLET+ T40 toilets utilizing Dual flush configurations Works with Washlet S7A and S7 bidet seatsbut not compatible with single flush setups or other Washlet models like S550e, S500e, or round seat S7A types. Installation is straightforwardsimply swap out