Item:Frequency range: 150Hz ~ 20KHzImpedance: ��600�� signal to noise ratio: ��65dBDistortion rate: <3%Material: ABSDimensions (mm): 210 �� 70 �� 67Packed Weight: about 500gI / O: Audio input: Bluetooth + Card / U disk / 3.5mm audio (AES / EBU inputs)Operation function (key): mode， volume addition and subtraction [+ -]， down song， play， pause