WEST BIKING USB Rechargeable LED Smart Sensor Waterproof Bicycle Rear Light

features auto/off, 7 lighting modes, 180 wide field of view, waterproof and dustproof. It is a great accessory for bike riding.
Features:
Brake light: Turn to high light automatically to warn the pedestrians and vehicles when braking.
Auto on/off: With high-precision smart sensor, the light turn on automatically when sensing the vibration, and switch off automatically when there is no operation in 3 minutes.
7 lighting modes: Easily switch among 7 lighting modes with a simple press of the button.
Much safe riding: 180-degree wide field of view and up to 100 lumens of brightness ensure good visibility and safety when riding at night.
USB rechargeable: Built-in 500mAh battery lasts for 5-15 hours after fully charged.
Waterproof: Made from PC plastic, lightweight, waterproof and dustproof.
Easy installation: Easy to install on the seat post of your bike with the included rubber rings, no tools required.