Synthetic-and-meshImportedSurface: 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 Ripstop? nylon uppers with increased drainage near toes and midfoot. Lace-up closure. Foot-shaped toe box allows naturalIf your running adventures take you to rocky and muddy environs, the King MT 1.5 from Altra? is prepared to tackle it all!Predecessor: King MT.Support Type: Neutral.Cushioning: Lightweight, flexible response.