TravelMate Extra-Large Memory Foam Seat Cushion &ndash; Perfect for Office Chair and Wheelchair &ndash; Does Not Slip EVEN on Smooth Marble Floors &ndash; Washable & Breathable Cover &ndash; Relieves Back Pain &ndash; 19&rdquo;x17&rdquo;x3&rdquo; EXTRA-LARGE COMFORT: The extra-large size of the TravelMate Memory Foam Seat Cushion means that pressure is spread over a larger area, giving you a more comfortable fit. Each premium memory foam cushion is 19 x 17 x 3 to fit a variety of seats. BREATHABLE MEMORY FOAM: Our extra-large cushion is covered with a layer of 3D ventilated fabric to disperse heat over a thick layer of premium memory foam, so you wont experience heat buildup even after hours of sitting. WONT FLATTEN OUT: Give the TravelMate Extra-Large about a week to conform to your shape, and youll experience custom-fitting comfort every time you sit on it without the eventual flattening effects of inferior memory foam cushions. NON-SLIP COVER: Theres nothing worse than your chair cushion sliding around, so weve added a non-slip silicone layer at the bottom of our extra-large cushions to keep them in place. Weve even tested its non-slip abilities on a smooth marble floor! RELIEVES BACK PAIN: Firm enough to support you and soft enough to be comfortable, TravelMate will support your whole body while sitting. It comes with a convenient carrying handle attached so you can take the comfort and support anywhere.