The ZWB-500 is a remote speaker microphone, slightly smaller and lighter than the ZWB-600. It has a rotary volume control which is easy to use, even when wearing gloves. With more than 40-hours talk time, the ZWB-500 is a real workhorse. It features a broad-range rotary volume control, 3.5mm jack for external earphone, and rechargeable battery. Comes with universal USB wall charger and cable.