Califone personal PA system is perfect for leading groups of up to 20 people, the Bluetooth VoiceSaver is for tour groups, presentations, athletic and dance classes. It"s ideal support for those needing either a vocal assist or increased projection. The lightweight wireless headset for the VoiceSaver enables hands-free convenience and operability from up to 20 ft away from the receiver. Its rechargeable battery will function for up to six hours on a single charge and refreshes in four hours. Optional wired mic sold separately.