AristaComfort Coccyx Cushion- Heart Shape Wedge, Deep Blue Design patented FIRM coccyx cushion. Compression-proof design upto 250 lbs. Unique design with a cut-out relieves pressure on coccyx (tail bone) and reduces stress on your spine. Raised rear end of the cushion raises your hips above your knees, taking the stress off from rest of the spine. Tapering front end ensures your legs dont go numb due to the front end of the cushion pressing the vein under the thigh. Firm closed cell engineered foam will not squish down even with weights of 150 lbs and above.