The beads, marketed under the name Arpo by JSP International in Detroit, provide impact protection andcooling. When a player wearing a Brock jersey is struck on the chest, each bead moves, trying to moveadjacent beads, thus deflecting energy away from the body and dissipating it over a larger surfacearea. The beads also let air circulate completely around them. Then, as the body sweats and watercoats the beads, the improved airflow accelerates evaporation, body cooling, and drying.