ONE SIZE FITS MOST ADULT KNEE: The big hole center fit the knee circumference 3.5''-9'' and the small hole center fit the knee circumference 1.5''-6'', knee cast cover 17''. Suitable for most Adult knee. ONE SIZE FITS MOST ADULT:The hole use the baggy design was intentional to make sure one size fits all customer requirements.suitable for most men and women. REUSABLE&HIGH-QUALITY:The knee protector uses an elastic rubber seal with easy to use pull-tabs. Reusable, washable, hard to be torn,Made of high quality PVC, polypropylene and rubber,Light, hygiene,waterproof knee cover will protect the bandages and wounds well. SAFETY AND EASY TO USE: Tough and durable waterproof knee cast cover protector for knee. Elastic rubber flange will not cut off blood circulation.Easily slide on the leg cast cover before bathing or showering to prevent water from damaging your cast and irritating your skin. 100% WATERPROOF:Waterproof knee cast covers for shower, when you take a bath or shower, knee cast cover keeps your bandage and wound out of the water and virus.