It is compatible with most of the classic toilets; from most round shape toilets.
Pepe Raised Toilet Seat with Handles, Riser for Elderly 4 inch Padded Hand Rails
Pepe Raised Toilet Seat with Handles, Riser for Elderly 6 inch Padded Hand Rails
Raised Toilet Seat with Handles, Riser for Elderly Padded Hand Rails
4" Raised Toilet Seat with Handles & Lid, for Elderly & Disabled Adults
