An external outdoor antenna is connected via cable to significantly improve reception. Position the antenna according to the included instructions. The phone remains on the front of the mobile power box during the call. You can talk using a headset or the hands-free function. The box is compatible with all networks. Antenna connection: SMA sockets. The mobile power box is designed exclusively for use with mobile phones. USB sticks are not supported. The phone is simply placed on the box and not secured.