My husband ordered the wrong size and forgot to return. Shoes have only been worn once. The new Trail Traction Outsole provides more grip on the trail, with a slightly higher stack height, providing a bit more cushion for more sensitive feet, yet they won’t weigh you down. The lightweight materials include an air mesh upper that allows for maximum air flow to wick away moisture and keep you presentable for a post-run brewski. The Primal Pursuit features the same zero-drop heel and wide toe box as the Primal 2 that allows the toes to behave like they are meant to - free and splayed.