Interface type: Card readerBattery capacity: 800Frequency response range: 100HZ-20khzSNR: ≥75dBPower supply: Built-in lithium batteryTrack: 2.1Running Time: 2 hoursExtended storage: 32GBBluetooth protocol: 4.1Number of speakers: 1Effective distance: 10 mFunctions: Card insertion, radioOperation mode: press the buttonApplicable people: GeneralShell material: metalSupported format: Usb flash driveSpeaker adjustment mode: button