HFS may be short for Happy Feet Shoes, Hyper Flexible Soles, or, more likely, what you will exclaim when you try this 7.0 ounce (M9) true road runner, Holy ___ ___! Your feet will love the natural comfort of the wide toe box and zero-drop design. The tire-inspired tread keeps you sure-footed. The 37.5 sockliner and breathable engineered mesh keep you cool. Hidden instep and mid-foot tensioners give you the security you need to go for that new personal best

Light, Grippier, and Comfier
Like the original HFS, the HFS II is super lightweight (8.3 oz, M9) so you’ll feel like you’re flying down the road. And with a new tire tread-inspired outsole, you’ll feel secure even if you go off road.

HFS II is so comfy, you might forget to take them off at the end of your run – we’ve even had people go to bed still wearing their shoes because they forgot they had them on!