Supportive Firm In order to provide enough support for your tailbone,the seat cushion feels harder than ordinary office chair cushion.When you use cushion for the first time, you may think the donut pillow is hard, but after using it for 1 to 3 weeks, you will realize the benefits of such hardness and like it. Ergonomic Design Seat Cushion for Male and FemaleThe Donut cushion is designed according to the different of the female and male 's body structure to make you feel more comfortable. Relieve Pain If you are suffering the pain of Tailbone, Hemorrhoid Treatment, Bed Sores, Prostate, Coccyx, Sciatica, Postpartum,please don't hesitate to choose the donut seat cushion,it will make you release from these pressure relief. Being Used Everywhere The donut seat cushions measurement: 17.5" x 16" x 3";The memory foam back cushion can be taken to anywhere you go ,and is suitable for any chair- wheelchair,office or home chair,seat of airplane,trains,car...etc