Get Behind The Shield With The Armor All Bluetooth FM Transmitter and Car Charger. It can be easily added to any car without any type of installation or wires, simply just plug into a car outlet. The voice assistance and built-in microphone with echo reduction allows you to drive safe and keep your eyes on the road with convenient hands-free talking. The transmitter uses FM radio frequency to pair to Bluetooth, allows access your smartphone's voice commands with one button, and wirelessly streams music to your car stereo. Best yet, the 3.4 Amp Dual USB Ports lets your charge up to two devices at once.