... meter,single wire,cord diameter 2.2mm(some models are two wires)Speaker:30mmImpedance:300 Ohms+/-10% at 1,000 KhzFrequency ... db at 1,000 HzChannel unbalance:<3 dBPlug: Two pin plug (single pin plug,bending plug,folding plug available)Company instruction1.JIANGYIN LIKN INDUSTRY CO.,LTD is ...