DescriptionThe FireFly Running & Biking Safety Lights help you be seen and stay safe in the dark. With its unique adjustable "flex" design, one size fits all for men, women and children's shoes. The FireFly has 2 light modes to choose from: 1) Always On, or 2) Continuous Flashing. With a high-intensity light, it allows you to be seen at long distances in the dark. It provides 100 hours of continuous use before having to replace the battery. These light spurs are comfortable and super lightweight so you won't even know they're there. Be seen and stay safe with the FireFly.