Size 1 fits bicep circum. 8.5 -9.5 * Uniquely designed knitted shoulder support guides and centers the glenohumeral joint promoting mobility but inhibiting rotation for proper therapy helping to keep the arm in the socket * Adjustable anatomically contoured silicone insert lies on the shoulder provides intermittent compression of the soft tissue leading to increased circulation and decreased pain swelling and subluxation * Anatomical knit with graduated compression at the edges prevents constriction of circulation * Lightweight breathable knit will not retain heat and sweat * Ideal for shoulder pain rotator cuff rehab shoulder subluxation post surgery osteoarthritis and hemiparesis * Universal - Can be used on either the Right or Left Shoulder * Machine washable * Size is determined by loose circumference of the biceps while arm is hanging loose