The Seat Bottom and Back Upholstery is a part for the Featherweight Manual wheelchair, 13.5 standard adult size only. It is sold as a set of one seat bottom and one seat back, and both are in the original black fabric of the featherweight wheelchairs. The set connects to the outside frame and is not sold with hardware or the fabric handles. The seat bottom and seat back fabric set is compatible only for the Featherweight manual 13.5lb wheelchair at a seat width of 18" and a seat depth of 16" (the heavy duty Featherweight extra wide manual wheelchair has a different size seat and this part is not compatible to the HD version). This seat upholstery set is for both the grey frame and matte black frame versions of the Featherweight Manual wheelchair.