Arrela E2 Bluetooth4.0 On-ear Headphones Wireless Headsets with Microphone and Rechargeable Lithium Battery Compatible with Computers, Tablets, Smartphones, iPhone, iPad Advanced Bluetooth 4.0, compatible with virtually any Bluetooth-enabled devices. Clear, high-definition sound, enjoy the pure music. Outstanding Bluetooth connection range of 10m. Built-in rechargeable Li-ion battery, lightning fast charging time. Built-in microphone provides hands-free phone calls.