... lights up, says voltage in 7.6V between 8.25V, power between adequate.*Blue light up, says ... voltage than 8.25V, full power.4. Vacuum plating mirrir reflective ... Used 4*18650 battery pack, capacity: 4400mAh, voltage:8.4V, work continuously 3 to 4 hours.7. Feature ... various types of bikes, easy to remove the replacement.8. Note: A. Charging put in safe place B. ...