The Sweet Protection Back Protector Vest 2. 0 for Juniors uses 3S Shock Shield foam, shaped to contour a kid's back with three layers over the most critical areas and two layers lower down for easier movement. Ventilation holes route around the spine and a 3D mesh lining sits against the skin, so the foam pad stays cool instead of trapping heat. A Velcro waistband and stretch woven shoulders keep the fit snug and adjustable as a kid moves, and the foam pad removes for easy handwashing. What Our Gearhead(R) Experts Are Saying:"My kid wore this under a jacket for a full day on the hill and never once asked to take it off. The mesh lining keeps it from feeling like a stiff plate strapped to their back, so the protection actually stays on instead of getting left in the car."