Use with any chair to stimulate legs and feet. Smaller size uses less space and fits better under desks and tables. Rock & stop design gives users more control, allowing the foot rest to be paused at various angles for optimal comfort. Anti-skid feet ensure the rocker stays in place. Vinyl covered medium-density fiberboard is easy to clean and very durable. 11-1/2"L x 17-1/2"W x 3-1/2"H; 4 lb.