Description Features of the Corflex Boxer Splint:Anatomically designed to provide comfortable support, protection and immobilization of the 4th and 5th metacarpals.Indicated for treatment of acute or sub-acute fractures of the 4th and 5th metacarpals commonly referred to as "boxer fractures".Constructed of lightweight low-density polyethylene shell with soft foam liner and palmer pad and contact closure straps.Wrist circumference: 5"-6".4th & 5th MCP joint: 3.25"-3.75".