CPCC-5 CHEST PROTECTOR FEATURES: All new chest protector design meets NOCSAE Standard for Commotio Cordis New 3D Airsmesh Delta Flex(R) Harness design for a dialed in fit with even more mobility CON4M(TM) Fit system includes the industry's first molded harness loops for quick attachment. 3DU Bar(TM) technology increases the blocking area by 50% to keep blocked balls within arm's reach. Tough bounces to the sides that would normally result in the ball getting away are instead redirected by the 3DU Bars so you can recover the ball and keep runners from advancing. SEI certified to the NOCSAE standard SIZING & ADDITIONAL DETAILS: MED: Chest Protector: 15.5" Chest Protector treated with StinkStop(TM) antimicrobial agent to keep you fresh