Connect with the ground like never before when you blaze a dusty path in the Altra Zero Drop™ Superior 2 trail-running shoe.Altra Zero Drop recommends that those new to natural running and zero-drop footwear transition slowly by wearing these on shorter runs and gradually building up to regular mileage.Built for the neutral runner seeking light underfoot cushioning. Ideal for trail running, hiking, fastpacking, and trail racing. Designed to improve running form, toe splay, stability, traction, comfort, and trail protection. Breathable, quick-drying mesh and synthetic upper materials. Lace-up closure. FootShape™ toe box allows the toes to relax and spread naturally for optimal comfort, speed, and stability. Lightly padded tongue and collar. Breathable fabric lining offers a great in-shoe feel. Removable 5 mm foam insole. Zero Drop construction places the heel and forefoot at the same distance from the ground to encourage natural, low-impact running form. INNERFLEX™ grid-like midsole flex grooves add flexibility right where it's needed to promote speed and enhance performance. Ultralightweight, dual-density Abound EVA midsole foam and a unique energy-returning compound work together to protect feet upon impact.TrailClaw™ outsole features canted lugs directly below the metatarsals and toes for maximum traction over a variety of terrain. StoneGuard™ provides flexible protection to protect from stone bruising. Total Stack Height (total thickness of midsole and outsole underfoot): 21 mmImported.