QuietComfort 3 Replacement Audio Cable Compatible with Bose QC3 HeadphonesReplacement Extension Audio Cable Cord for BOSE QuietComfort3 QC3 Headphones Features: -You can use it to connect any device with diameter 3.5mm to listen to music. -It has 2 types of ports, 2.5mm 4pole male stereo plug and 3.5mm 3pole male stereo plug. -It is light and small..