IPX4 water-resistant Powered with 2 x 3V Lithium 2032 batteries Burn Time: Steady on - 57+ hours, Strobe - 110+ hours Be seen and stay safe on your night time runs with the Nathan Strobe Light. This slim, lightweight and waterproof light helps you stay visible in low-light conditions. It has a secure clip on the back to easily attach to your gear. It is IPX4 weather-resistant so you can run longer in any weather. The light provides a high degree visibility for as long as you need it, with both blinking and steady light modes. The replaceable lithium batteries last over 110 hours on strobe mode or over 57 hours in steady mode.