The Original BD21 Multi-Position Inflatable Chair (4 Wedges = 1 Chair) Adjustable to individual firmness & relaxation - helps relieve stress. Cradles and moulds to the contours of the body - especially supporting the back. Helps reduce pressure on the spine. Helps create the sensation of true weightlessness. Completely portable, use virtually anywhere e.g. on the couch, the floor, the bed, the beach, next to the pool, outdoors, etc.