7/8″ x 7/8″ x 1/2″, Plastic Nut Generic Bidet T-Valve (OLY-11) Can be used for most bidet seat installs when installing the T on the bottom side of the toilet tank.
Olympia Bidet Parts
Generic Bidet T-Valve, 7/8″ x 7/8″ x 1/2″, Plastic Nut (OLY-11)
$25.99
Can be used for most bidet seat set ups