16 Core 99% Silver Plated 2.5mm 3.5mm XLR Balanced Earphone Cable For Sennheiser HD580 HD600 HD650 HDxxx HD660S HD58x HD6xx. 3.5mm 3 pole (Stereo) Plug. 3.5mm 4 Pole balanced plug. 2.5mm 4 Pole balanced plug.
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