High-visibility & Weather resistant - Our compact rear bike tail lights are designed to be visible from up to 1500 feet away, making them an essential safety accessory for night riding. The bike lights have IPX5 protection to withstand wet conditions. Lighting Modes - Choose between Steady and Flashing mode with just one click on the super bright taillight, our red bike tail light is perfect for different riding conditions and your safety. Flexible Use - In addition to being great for bikes, our bicycle light can also be mounted on car bike racks, wheelchairs, strollers, and more. A multi-talent for your everyday life. Each light needs 2 AAA batteries. Easy installation - These LED bike lights can be easily installed on your handlebar and the seat post of your bike with the included quick-release mounts (strap or screw mount). Also the bike rear light can be opened without tools using only a coin. Requires two mounting hole to attach. BV Promise - We invest a lot in the high quality and reliability of our products, but unfortunately we cannot completely rule out problems. If you have any problems with our product, please contact our customer service and we will find a solution for you.