1/8” Neoprene provides compression Brace fits left or right hand Aluminum stay and steel spiral stay are interchangeable and removable Ideal for treating Basal Joint Arthritis, Throttle Thumb, and thumb tendonitis Elasticized patient assist strap makes one handed application easy Taping above stay allows trimming for freedom of the IP joint Sizing: Standard - Thumb hole 2.375"-3.0" and Wrist circumference 5.0"-9.5" XS - Thumb hole 2.125"-3.375" and Wrist circumference 4.5"-5.5" XL - Thumb hole 3.0"-3.625" and Wrist circumference 5.0"-9.5"