A:AnswerThey come with a USB charging cable. I charge mine using the computer, but if you have a wall USB or car USB charger, you can charge them that way as well. The LED light on the back of the removable flex collar will turn red when they need to be charged (also will hear a beep if using when battery gets low). When fully charged the LED light will turn blue. Takes about 2.5 hours to fully charge via the computer when they are out completely drained of battery.
