X-Strap- The X-Strap fits over the brace and helps to keep it in place on the shoulder. Provides superior compression and support for past shoulder injuries, Adjustable arm closure design eliminates underarm chaffing, Universal no snag design fit, Easy on / off design, Breathable air mesh construction with TPR gripper pull-tabs, X-Strap Stabilizer System provides double shoulder support. Available in Sizes: S, M, L, XL, and XXL. Need to see how to measure for this brace? Check out our sizing chart