A fan favorite for race day and daily training, the Topo Athletic MTN Racer 4 offers rugged performance on technical trails. A 33 x 28 mm platform delivers underfoot cushioning and a protective barrier between you and the ground. Our new upper is fine-tuned for performance on technical terrain. The MTN Racer 4 now features our FKT insole, allowing for faster water drainage and added rebound, while our improved gaiter attachment system keeps out debris. The VibramA(R) Megagrip outsole provides reliable traction and durability, delivering serious performance when the trails get gritty. Compatible with our Switchback Gaiter. 5MM Drop Our highest available drop allows you to access natural running with more under-heel cushioning. Gaiter Compatible Offers additional protection from dirt, rocks, and twigs on the trails Roomy Toe Box Anatomical toe box allows toes to spread naturally and comfortably. Vibram Outsole Unparalleled grip and traction and durability from the leaders in technical outsoles.