Sparco Rib Pro K-4 Rib ProtectorThe Sparco Rib Pro K 4 adds protection and padding without bulk, through the use of Sparco Impact Technology, a 4mm thick EPDM material mated to a 6mm PU foam. This combination equally protects against high energy impacts and provides vibration dampening. A thermoplastic shell is then applied to this material to provide increased impact protection. Special cutouts greatly help increase breathability, while rubber edging on the shell helps reduce wear