Tricky trails are no match for the rugged design of the Altra® Superior 3 trail-running shoe!Predecessor: Superior 2. Support Type: Neutral. Cushioning: Lightweight, flexible response. Surface: Trail.Differential: 0 mm.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.Ideal for trail running, off-road racing, hiking, and backpacking. Designed to help improve natural running form, walking form, and toe splay. Quick-drying air mesh and thin synthetic upper materials. Lace-up closure. Foot-shaped toe box allows natural foot flex and toe splaying.GaiterTrap™ hook-and-loop tab allows for gaiter attachment.Heel pull loop.Padded tongue and collar. Breathable fabric lining offers a great in-shoe feel. Removable 5 mm Contoured footbed. Fully cushioned Zero Drop™ technology promotes a more natural foot strike for a more efficient stride.EVA and A-Bound™ blended midsole with InnerFlex™ provides impact protection and energy return with each stride. DuraTread™ and TrailClaw™ outsole features canted lugs beneath the metatarsals for ultimate gripping in the gnarliest of terrain.Stack Height: 21 mm.Last: PFS2-M/PFS-W.Imported. Measurements: Weight: 11 oz