I am sitting on a seat cushion (Seat Large) and a Back cushion (Back & Seat) and writing. It is supportive and provides good relief in the back and in the seat. When I get the wheelchair I will try it out there. In the car, I have tested your “nursing cushion”. It gives me relief in my arms and shoulders.The biggest advantage of your products is that they do not weigh quite a lot and they are easy to bring along.