The official shoes worn by 2014 Boston Marathon winner Meb Keflezighi, Skechers Go Meb Speed 2 running shoes don't have any extra material or weight to slow you down. The 4mm heel-to-toe drop places your feet in a nearly neutral position for increased comfort and efficiency. A seamless interior with a microfiber lining provides maximum comfort in motion. These shoes are built for competitive racing and designed for speed.Upper: Flat laces reduce irritation and pressure points. Printed, nearly seamless mesh fabric is lightweight, smooth and flexible. Padded heel collar enhances comfort. Comes with an additional set of laces.Midsole: M-Strike Technology™ promotes a midfoot strike. Rosalyte™ midsole proprietary lightweight injection-molded compound with memory retention helps absorb impact. Dupont Hytrel™ Stability plate in midfoot delivers a supportive and secure run. Outsole: Independent circular GOimpulse sensors offer a more responsive running experience.