VicTsing Wireless Bluetooth Headset for Car Truck Driver, Over-the-Head Wireless Hands Free Headphones with Mic for Call Center, Operators This is a new wireless Bluetooth Stereo Headset, which uses an over-the-head design and has been using Bluetooth wireless technology. And, it is capable of connecting with Bluetooth devices designed with Audio Gateway and PDAs. Standard Convention/Signal input: Bluetooth V2.1, Class 2; Frequency Band: 2.4 GHz-2.4835GHz, ISM Band; Talking/Standby time: up to 8 hours/Up to 200 hours Supporting profile: Headset and Hands-free; Connection: Peer to Peer; Data Encryption: 128 bits encrypted; Working range: up to 10 m Power Capacity: Rechargeable Li-Polymer; Power supply: DC 5V, 100-240V AC adapter(Not included)