Feature:1. LED lights, energy-saving, high-brightness, made of silica gel, are relatively soft and not easily damaged.2. It is easy to install and can be directly hung on the rail, line pipe, or other positions close to the pipe body under the seat cushion.3. It can be installed behind the car seat as a tail light, or installed at the front fork line of the handlebar as a front car warning light. The colorful design makes it safer to ride at night.4. Three flashing modes can be selected, including fast flashing, slow flashing and long time light.5. Because of its small size, you can easily carry it, with a special case that is waterproof.Specification:Item Type: Bicycle Seat Tail LightMaterial: Silicone+PlasticSize: About. 6x3.5cm/2.4x1.4inBattery: 1 x CR2032 button battery 200mAh (included)Lighting Mode: Fast flashing, slow flashing, always on lightNote: When replacing the button battery, please do not be too violent.How to Use: 1. Unscrew the rubber cap;2. Take out the battery cover;3. Replace the battery;4. Put back the battery, put on the outer cap, and the test light is on or not. Package List:1 x Bicycle Seat Tail LightNote:When replacing the button battery, please do not be too violent.