The new high-quality bicycle lights， lamp beads for high brightness LED material.Rechargeable polymer lithium battery - Luminance: 15LM (low power consumption and durable service).USB rechargeable bicycle taillight and auto cut off when fully charged.O-ring strap suitable most bike cube(12-32mm) ---- Modes: Long bright/Slow flashing/Shun flashing/Strobe.Waterproof Usb Rechargeable Flashing Night Rear Tail Flashlight Warning Cycling Bicycle.Great for student， baby stroller， jogging， walking， bicycles， car emergency， horse-riding， road emergency&camping， ETC.High quality internal lithium battery，only need about 2 hours to be fully charged while be used for about 12 hours.Super waterproof， make you riding freely regardless of rain.High brightness and energy saving LED.Specifications:1. Mode: 4 modes2. Brightness: 15 lumens3. Item Color: Black4. LED Light: As the picture shown5. Product Dimension: 7.5*3*2cm6. Mounting Placement: bicycle seat post7. Type: LEDs8. Suitable Tube Diameter: 12-32mmRunning time:Long bright: 4 HoursSlow flash: 10 HoursShun flash: 12 HoursStrobe: 8 HoursThe charging time is about 2 hours.