Ultra High Visibility - Runs on a small button battery, and the LED lights and polymer for light transmission ensure extremely high visibility for twilight and nighttime activities. The brightness is much higher than the glow of the dark glow sticks. That means more security for you, your children or your pet from careless and distracted drivers. Three Lighting Modes - The light strip has three lighting modes: Fast flashing, slow flashing, always bright mode. Just one click to control. Easy to use. Suitable for all your favorite outdoor sports, such as cycling, jogging, running, camping and walking. Freely Adjustable Size - The running reflectors, which length is 28-32cm, is adjustable, suitable for most men, women and children. You can wear them on your wrist, ankle and arm. Quick to put on and very light, with good quality and comfortable material, the jogging light strips are the ideal complement to the reflective stuff, perfect sports accessory. Replaceable Batteries - Powered by two pcs CRV2032 lithium button cells, the led bracelet can work about 60-80 hours. Normal use for 2-3 months, battery can be replaced by yourself, we will give you 4 extra batteries Package includes: 2 Led Bracelets(red)and 2 Led Bracelets(green) Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.