Small Fits circum. 12 - 13.5 Elastic Support for Prevention Treatment & Rehabilitation of the knee Thermoskin elastics can expand contract and stretch and are made of a high-grade durable material that permits a full range of movement and are comfortable to wear during a range of activities. Anatomically designed with no seams this four-way stretch support combines Spandex with hosiery technology to provide protection and support for weak and injured knees.