1 Cable diameter: The diameter of the main body cable is 5mm and the diameter of the branch cable connected to the earphone is 3.2mm.2 Connector: 4.4mm Balanced Male to the Jacks for HD650 HD600 HD580 HD660S HD58X Massdrop HD6XX Headphone3 The connectors shell are made of the walnut wood / Solid Wood - Walnut + Brass Gold Plated4 Replacement audio Upgrade cable with 4.4mm Balanced Male Walnut Wood Shell 7N OCC copper Single Crystal Silver Plated Cord 4.4mm Balanced Cable Compatible with Sennheiser HD650 HD600 HD580 HD660S HD660S2 HD58X HD565 HD545 HD535 HD525 Massdrop HD6XX headphones Extension Cords5 The 7N OCC copper Single Crystal Silver Plated wires provide clear sound and a protective layer is added to eliminate noise interference problems you will enjoy matchless HiFi sound and maintain original sound quality of your headphone Extension Cords6 Package include:1*replacement audio cable