The ECM-HW2 from Sony is a complete battery-powered bluetooth wireless microphone system. It mounts into the active interface shoe of a Sony Handicam camera, and enables you to capture the subject's and the camera operator's voices from up to 300 feet (91.44 m) away. If your camera does not feature an active interface shoe, the ECM-HW2 will not operate. However, if your camera has a standard 3.5 mm microphone input jack, you can use the Sony ECM-AW3 for this purpose.

There are two operational modes for this system. You can choose to have the built-in microphones pick-up both the voices of the subject, and the device operator. For example, if a child is wearing the transmitter while running around a playground, the microphone will pick-up the child's voice, and the microphone on the receiver will pick up the sound of parent's laughter and commentary.

You can also choose to use this system with the microphone on the receiver disabled. This is useful in situations where you want to focus the attention on one subject. For example, when shooting a business presentation, the camera operator can whisper cues to the on-screen talent without being heard.

The ECM-HW2 also doubles as a two way communication system. It includes two sets of earphones that plug into each module, so both parties can clearly hear one another. A belt clip and an arm band are included (the arm band enables you to attach the transmitter to a subject that is wearing clothing that cannot accommodate a belt clip). An included carrying pouch will help to protect the transmitter.