Rarely used. Used indoors only and for less than 15 miles (I realized I am not a runner!). Excellent amount of tread. Engineered with Rapid Roll technology that enhances propulsion, this nitrogen-infused running shoe will have you flying around the track. From website • Neutral: provides soft, even cushioning with an emphasis on comfort during any activity • Lightweight: puts cushioning and performance underfoot with an emphasis on streamlined comfort • 3D Fit Print mesh upper provides a soft, comfortable fit as your stride expands and contracts • Rapid Roll technology curves every stride from heel to toe to propel you forward and amp up your speed • DNA FLASH nitrogen-infused midsole fuses explosive energy return with a lightweight, adaptable fit • Removable insole • Textile upper and lining/rubber sole • Imported