The silky kapok fiber, or floss, is actually a tiny cellulose tube with air sealed inside. The material is removed by hand, dried, separated from the seeds and prepared for export. It is too brittle and inelastic to be spun, but it is ideal for stuffing life preservers and other water-safety equipment because of its excellent buoyancy. It can support as much as 30 times its own weight in water and loses only 10 percent of buoyancy over a 30-day period. Kapok fiber is also a popular stuffing for pillows, mattresses, upholstery, sleeping bags, quilts, and jackets because it is lightweight, non-allergic, non-toxic, and odorless. The fiber is an important export of the Indonesian island of Java, and is often referred to as Java cotton. Recently, however, foam rubber, plastics, and man-made fibers have started to replace kapok fiber.