Rawlings Youth Zoombang Heartguard Baseball Shirt , Youth S 
Rawlings Youth Zoombang Heartguard Sleeveless Baseball Shirt The Zoombang Youth Baseball Compression Shirt is based on a unique energy dissipating material called Zoombang Polymer. These padded shirts are thin, lightweight, and provide the athlete with a layer of conformal cushioning and support, yet react to help dissipate energy when an impact is applied. Zoombang Polymer is a new viscoelastic polymer that is a soft, pliable liquid at rest. However, when a sudden shear force, such as shock, is applied the material immediately changes physical characteristics and stiffens to dissipate the energy. Once the force has passed, the material transforms into its original conformal cushioning state. Sizes: Youth S,Youth M,Youth L. Color: White only.