Model Number: AKB-BSH508P Key Specifications/Special Features: Sports in-ear Bluetooth earphoneCSR 86451.Compatible with all audio equipment with Bluetooth functions, such as PC, iPad, iPod, cellphone, tablet PC, MP32.HSP, HFP, A2DP, AVRCP3.Bluetooth protocol standards: Bluetooth V4.1 supported4.Receiver distance: 10m/360°5.Battery: chargeable 3.7V/100mAh lithium-ion battery6.Charging time: less than 2 hours7.Successive working time: about 6 hours8.Standby time: 180 hoursDirectivity: whole directionSensitivity: S.P.L: -42±3dBImpedance: ≤2.2KΩFrequency response: 30-16,000Hz