Bluetooth version: V4.1Waterproof grade: household waterproofBluetooth connection effective distance: about 10 metersInput voltage: DC5V / 1A (Micro USB interface)Battery capacity: 400mAhPlaying time: 2-3 hours (high volume).Speaker power: 3WNominal impedance: 4 ohmsSensitivity: 800mVBluetooth operating frequency: 2.402GHz-2.480GHzSpeaker frequency response: 100Hz-20KHzFunction: Bluetooth music player, Bluetooth connection, call functionPurpose: mobile phones, tablets, laptops and other devices with Bluetooth