AliMed Easy-On Elbow Brace features an adjustable extension/flexion stop with a range of 0?° to 135?° in 5?° increments. Tool-free adjustment. Simply rotate the cover to expose the stop pins and reposition them as required. Cushion cuffs are thick, self-padded, washable fabric with hook and loop fasteners. All joints feature fully cushioned protectors. Fits left or right. Sizing: Measure circumference at belly of forearm and biceps. Small fits forearm 8" to 10", biceps 9" to 11" Medium fits forearm 10" to 12-1/2", biceps 11" to 13" Large fits forearm 12-1/2" to 14-1/2", biceps 13" to 15-1/2" Specify item number and size.