Connectivity\r\nWireless and cordless headsets operate without a cord. Wireless sets will have a transmitter (base) which sends a signal to the headset which in turn will have a built-in receiver and amplifier. "Wireless" sometimes refers to infrared-based systems and "cordless" to radio frequency (RF) transmission systems. Infrared systems have a relatively short range of 10M or so from the base unit and must be in "line of sight" of the base for clear reception. RF (Radio Frequency) systems can transmit up 100M from the base unit - even through walls.