Feel like your favorite speedy superhero in the updated Speed Force II. A 5.9oz (M9) racing flat, it won't complain if you wear it off the track for normal speed endeavors. With a sock-like feel, flexible 4.5mm FeelTrue® sole, and mesh upper, you might forget you're even wearing them. If you don't like talking to strangers, be careful in the Speed Force II - the eye-catching design with Xero's adjustable heel and instep strap system may make people stop you to find out where they can get a pair.