Topo Athletic Ultrafly 4 Running Shoe – Men's color-blue Wear the shell alone

Wear the shell alone

Sized-down padded shoulder straps and a padded back panel keep it comfortable on smaller frames

Relaxed women's fit works well over a base layer or under a shell for variable Southern mountain weather

Ribbed collar and cuffs add structure and hold their shape wash after wash

Extended cuffs close the gap between glove and sleeve — no exposed wrist skin on long sun days

Topo Athletic Ultrafly 4 Running Shoe – Men's color-blue Wear the shell aloneBuilt for daily training and long mile comfort on roads and pavement, the Ultrafly 4 is our top pick for runners who want a natural feel without sacrificing support. ZipFoam cushioning keeps the ride light and responsive, while the roomy toe box lets your foot move the way it's supposed to. At 5mm drop, it bridges the gap between minimal and traditional. ZipFoam midsole delivers lightweight, responsive cushioning across 30mm heel 25mm forefoot stack