ROHO Hybrid Elite Cushion Cover with two way stretch polyester top enables the cushion cells to conform to the individual's body shape without diminishing product effectiveness or therapeutic value. The side material is composed of a 3-layered knit polyester spacer fabric, which provides superior air circulation that ventilates and cools the user. The fluid proof, solid, non-skid base material offers a durable easy to clean surface and velcro straps to eliminate movement. Hand or Machine Wash. Warranty: 6 Month Limited Warranty.