Note: 1. Please allow 1?3cm error due to manual measurement. Thanks for your understanding._x000D_2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. specification: _x000D_Item Type: Seat Cushion_x000D_Material: Polyester Fiber_x000D_Function: A pressure-relieving seat cushion, comfortable to use, can relieve tailbone pain. Office chair cushion that can be used as a seat pillow and backrest._x000D_Product Size: Approx. 40 x 39 x 8cm / 15.7 x 15.4 x 3.1in Features: 1Oblique U?shaped grooves design, whole concave, wrap buttocks, comfortable to use. 2U?shaped grooves squeeze the muscles on both sides to the middle, wraps and relieves the buttocks, and also supports the pelvic bones. 3The cushion is not easy to be deformed, and the hard tubes on both sides press inward to keep the front of the cushion in the original curvature. 4Central round hole design can keep the air flowing in the buttocks and give the buttocks a refreshing and hygienic environment. 5Made of high quality fabric, soft and skin?friendly, eco?friendly and durable. Suitable for people of different body types. PackageList: 1 x Seat Cushion