Crystal Pure Red Rear Light. Featuring transparent light body and special internal reflecting patterns, TR30 gives out 360 degree beam with max 30 LED lumens, providing much better rear and side visibility to increase rider's safety. It is lightweight, easy to use and versatile with quick release clamp mount.   Features Dual Highly efficient LEDs with max 30 LED lumens. Transparent light body with 360-degree beam angle. Special internal reflecting patterns, enhancing the rear and side visibility and increasing rider's safety. Mounting angle adjustable for daily riding with max visibility or for group riding without dazzling following riders. Quick release design, compatible with round and aero seatposts. Micro USB charging port, compatible with most phone chargers. Built-in battery indicator and charging indicator. Intelligent memory circuit remembers the last used brightness level and mode when turned on again.   Specifications LED: Dual highly efficient LEDs. Battery: 200mAh/3.7V rechargeable Li-polymer battery. Dimensions: 25mm (L)*21mm (W)*62mm (H). Weight: 22g. Mount Size: compatible with 24-36mm seatpost. Design and specifications are subject to change without notice.