Bluetooth 4.0 and aptX technologies to deliver exceptional wireless sound quality ; Intuitive ear-cup mounted controls for changing tracks and for making calls via the integrated microphone,NFC for simple pairing with compatible devices ; Audio Cable Length (Optional/Detachable): 1.4 m audio cable, 3.5mm angled, gold-plated plug,Up to 25 hours battery life and is supplied with connecting cable for battery-free listening,Ear coupling closed, circum-aural; Dynamic transducer principle ; Product comes with Case,2 years warranty when purchased from an authorized Sennheiser dealer