Under Armour Charge RC II Racer Running Shoes Synthetic-and-mesh Articulated Upper Flex - To mimic and enhance natural foot movement and allows the foot flex for more natural. Super Lightweight - Weighing at only 141g, it is one of the lightest shoe ever and making your workout easier. Moulded 4D Foam Sockliner - Conforms to your foot's exact shape, eliminating slippage. Padded MPZ Tongue - A great modular protection zone desgined to help protect the upper of your foot from abrasion. Thick Collar - So you won't even feel this shoe around your ankle and reduce chaffing.