The Icebug Acceleritas5 RB9X Sneaker is a must-have for the thrill-seeking runner venturing into swimrun, obstacle race or beyond the beaten track! The upper materials have been updated to a super soft and airy textile, so light and smooth it feels like being barefoot. The height of the heel cup is slightly reduced in order to reduce pressure at the Achilles tendon. The shoe promotes the natural movement of the foot, it's like running in a pair of socks, but socks that provide thermal and impact protection and traction. The outsole is designed with a pattern that is optimized to grip on hand as well as on soft surface, with an aggressive pattern where dirt is steered away to the sides in diagonal channels. Upper: Polyester mesh/TPU mudguard Lining: Quick dry mesh/Micro Suede at heel counter Insock: EVA racing insock glued to insole Midsole: Compression molded Lightweight EVA Outsole: Rubber 9 Extreme (RB9X) Torsion: Easy Flex Drop: 4 mm Cushioning: Responsive Last: Narrow. 1361.