Nite Ize L.E.D. Sport Vest is a lightweight, fashion-friendly black mesh vest is made with 3M Scotchlite™ reflective material, and features two illuminated flexible polymer strips (front & back) that can be set to one of two bright LED Light modes: steady glow or flash. Wearing this vest when you're heading out for a run or ride in the dark is a comfortable, effective way to ensure you'll be instantly visible to oncoming traffic. Universally sized with easily adjustable hook and loop at the waist, the LED Sport Vest is easy to slip on and off. Power/mode buttons are easily accessible on the front and back of the vest, and elastic sections with hook and loop closure allow adjustment at the waist for a snug fit. Two long-lasting, easy-to-replace batteries are included.