Amazon.com: Sennheiser Genuine Adapter Cable Female 1/4" 6.3mm to Male 1/8" 3.5mm Plug for Headphones : Electronics
Amazon.com: Geekria QuickFit Audio Cable Compatible with Sennheiser HD 560 S, HD599, HD598, HD 598SE, HD 598CS, HD 598SR, HD579, HD569, HD400 PRO Cable, 2.5mm Jack AUX Replacement Stereo Cord (6 ft /
Genuine Sennheiser Headphones Extension Audio Cable 3.5mm TRRS M/F AUX Cord 4 FT | eBay