The Freedom Seat cushion by Contour Products (available at many outlets including Amazon) has 7 distinct features to improve your back comfort while seated.
The Freedom Seat’s wedge shape restores your lumbar curve and comforts spinal discs, while its coccyx relief cutout minimizes pressure build-up in the tailbone area. The cushion’s unique, cradling edge design positions your hips for better posture.
Shallow surface dimples combine with a breathable cover to enhance softness and allow better air ventilation. This cushion is made of highly resilient material to distribute your body’s weight more evenly, minimizing pressure points. Its anatomic shape and contoured surface comfortably fit you anywhere you go.
It’s great for home use and also with wheelchairs, in the car, or on the plane.
Coccyx Relief Cutout - The "Zero Pressure Tailbone Cutout" for coccyx area, minimizes direct contact between the sensitive tailbone are and the seating surface. This reduces uncomfortable stress and pressure which can build-up during prolonged seating.
Highly Resilient Material High-Density foam provides better support and even distribution of your body's weight, reducing uncomfortable pressure points around the pelvic bone.
I actually could not cope without my coccyx cushions for travel.