Bluetooth devices use Notes: 1 Charge: charging any brand of Bluetooth devices maximum time limit of 3 hours. Usually see the light color on the headset on or off can be a power. Long to the product charge, will it cause serious injury. 2, use: it would be better with the headset and phone on one side of the body, it is easy headset to receive cell phone signals. 3, if not a long time Bluetooth products, it is best to charge the device once a month or so. So that its built-in battery can not re-enter dormancy charge to use. Normally, all cell phone jammer should be installed in the position as per the predicted positions.