The Alpinestars Youth Bionic Rib Protector is ergonomically constructed to provide protection for the ribs and kidneys for today's young kart racers. Its lightweight design uses intelligently designed adjuster placement for a supremely comfortable, custom fit. The durable cordura construction incorporates dual-density, ergonomically shaped protectors constructed from a robust PE hardshell, with a fiberglass core for impact and shock dispersion.