Our zabuton is filled with a generous three inches of natural cotton stuffing. The cotton is packed densely enough to provide solid support, and yet is soft enough to provide great comfort. The outer cover is made of a sturdy, 100% twill cotton. The cover features a zipper along one length so that it can be easily removed and washed. Inside the cover, the batting is enclosed in a natural cotton casing. Each zabuton is 36" long by 28" wide by 3" tall