This bike tail light with adjustable lighting modes,is safe and perfect for outdoor riding use.<br/>Features:<br />SMART BRAKE SENSING: The smart tail light will automatically enter into slow flashing mode during your braking time,and automatically turn off when you stopping for 10 seconds.<br />HIGH BRIGHTNESS &amp; Multi-MODE&#xff1a;Bike tail light offers 7 lighting modes,includes low,medium,high,slow flashing,medium flashing,fast flashing and breathing flashing mode.<br />IPX6 WATER-RESISTANT&#xff1a;Made of plastic material,endurable and water-resistant.NOTE: Please do not soak into water fro long time.<br />USB RECHARGEABLE&#xff1a;Built-in 500mAH battery recharges from your power bank,plug or any device with a USB port.<br />EASY INSTALLATION: Saddle rail mounting bracket provided,quick to install or detatch on your bicycles.<br/>Specification:<br />Mounting Position: Seat Post / Saddle Rail (optional)<br />Color: Black / Pink / Multicolor (optional)<br />Material: Plastic &#43; Silicone<br />Waterproof: IP X6<br />Battery: 1 * 3.7 v 500 mAh lithium ion battrey(included)<br />Brightness: 100 Lumen<br />Lighting Range: 180 °<br />Light Size: 44 * 34 mm / 1.7 * 1.3 in<br />Light Weight: Approx. 56 g / 2.0 oz (with mounting bracket)<br />Package Size: 110 * 80 * 35 mm / 4.3 * 3.1 * 1.4 in<br />Package Weight: Approx. 80 g / 2.8 oz<br/>Package List:<br />1* Rear Light<br />1* USB Cable<br />1* Instruction<br />1* Mounting Bracket