It is great for cycling at night or in places where visibility and safety are concerns. 

• Built-in rechargeable lithium battery, only takes 1 hour to fully charge, and the working time is 3-12 hours
• White headlight with 4 switchable lighting modes, and rear light has 6 lighting modes to select
• IPX4 waterproof and charging port with a waterproof rubber cover, convenient to use on rainy days
• It weighs only 22g for each light, lightweight and portable
• Easy to install on your bike tube with provided rubber bands
• Wide application for seat posts, handlebars, backpacks, helmets, etc.
• Suitable for cycling, hiking, camping, or any outdoor activity

Specifications:

• Battery: (head light) 350mAh ; (rear light) 250mAh
• Waterproof level: IPX4
• Working time: 3-12 hrs
• Charging time: approx. 1 hr
• Size: 43.5 * 30 * 27mm / 1.7 * 1.2 * 1.1in
• Weight: approx. 22g / 0.8oz (for each)