The model EX RX is a bottom only and very popular for people that have the large executive chairs. Sitting for long periods of time is not healthy for your back or spine but this seat really helps.
For the larger person who needs support without the pressure in the tailbone area. Fits great in executive chairs. Sitting on this firm bottom forces you to sit up straight and does not allow your hips to go into the "C" shape.
We will be happy to assist you.