Sennheiser PXC270 Noise Cancelling Stereo Headphones Fold and flip - Registered design allows the ear cups to be turned through 90 and fold the headphones closed (headphones will lock in open and closed positions) Ideal for aircraft and railroad travel High-resolution sound due to Sennheiser Duofol diaphragms with spiral embossing 1.8 m Kevlar-reinforced OFC copper cable with 3.5 mm jack plug, delivered with an adaptor to 6.3 mm (1/4) stereo and 3.5 mm double mono (for airline audio)