The Supracor Stimulite Tension Adjustable Back, for both rigid and folding chairs, replaces a wheelchair's standard back upholstery. Sandwiched inside this wheelchair back is a one inch thick cushion of breathable Stimulite honeycomb material. Supracor—the manufacturer of this product—specifies this cushioned, adjustable wheelchair back upholstery as follows.
The product picture above shows; for a folding wheelchair, the tension adjustable back without its outermost cover. The outermost cover conceals the velcro-fastened tensioning straps.
The 16 inches high models (applicable only to folding wheelchairs) are affixed to the wheelchair back by wrapping around the canes—the vertically oriented metal tubes—of the frame. The back upholstery tension is adjusted by means of 6 fixed-position straps.
The 12 inches high models (applicable only to rigid wheelchairs) exhibit sleeves that fit over the canes of the wheelchair frame. The back upholstery tension is adjusted by means of 3 fixed-position straps, and a forth strap (with a buckle) that can be positioned at any height on the back.
Regarding back width sizes, the manufacturer's general counsel is that both a 14 inch and 16 inch wide Stimulite back will fit a 15 inch wide wheelchair, both a 16 inch and 18 inch wide Stimulite back will fit a 17 inch wide wheelchair, both an 18 inch and 20 inch wide Stimulite back will fit a 19 inch wide wheelchair, etc. However, people who prefer a bit less excess in the tension/width adjustment will generally prefer the more narrow of the two adjacent Stimulite back sizes. Similarly, people who prefer a maximum amount of adjustability will generally prefer the wider of the two adjacent Stimulite back sizes.
For example; a person whose wheelcair width is 17 inches, and whose preference entails a minimal amount of back tension/width adjustment, would generally prefer the 16 inch wide Stimulite Tension Adjustable Back. Conversely, the 18 inch wide Stimulite Tension Adjustable Back would generally be preferred by the same person if the person wanted a maximum amount of adjustability.