On Running Women's Cloudsurfer Running Shoe Acorn The flexible rubber outsole is

The flexible rubber outsole is durable and lightweight

Heel Height: 3 1/2"

firm leather by ECCO

Add to that ABZORB midfoot cushioning

On Running Women's Cloudsurfer Running Shoe Acorn The flexible rubber outsole isCruise the concrete in this ultrasoft road running shoe. With CloudTec Phase cushioning for a smooth ride and seamless heel to toe transition. THIS IS CLOUDTEC PHASE For an adapted and specialized version of our signature CloudTec technology, ON left nothing up to chance. Using Finite Element Analysis (FEA), they simulated how each component of their prototype reacts while running. Using invaluable insights from this method, they created the optimal