The picture is of an elongated circle that it meant to put on the toilet to raise the heat for easier standing from a seated position on the toilet
The image shows a toilet riser on an elongated toilet type

Elongated Toilet Seat Elevator

The Elongated Toilet Seat Elevator assists users with bending or sitting difficulties by adding 3.5 inches to the height of the toilet seat. This seat works in conjunction with your existing toilet seat and lid for a less clinical look. Fits most elongated toilets.

Installs under existing toilet seat. Adds 3.5" to the height of the toilet seat. Fits most elongated toilets