A complete wireless headset microphone system for fitness includes a headset microphone, a wireless transmitter, and a receiver. AV Now also offers individual components if you're not looking to start from scratch. Some of these mic systems have a bodypack transmitter, and some have the transmitter mounted to the headset frame, which has become increasingly popular for aerobics instructors, especially cycling instructors. In either case, they are all considered wireless microphone systems. We came up with the term cableless to describe systems, such as the Samson Airline 77 and the Special Projects EVO, that have the transmitter on the headset frame.