Product Description: With the ATH-CKR55BT’s newly designed 10.7 mm drivers and Bluetooth® wireless technology (including access to the high-quality aptX and AAC codecs), you get powerful, full-range audio that goes wherever you go. The headphones also feature an in-line mic and controls, allowing you to answer calls, adjust volume and handle playback of music and videos on compatible smartphones and other devices, plus a built-in amplifier to enhance the audio’s depth and resolution. Machined brass stabilizers absorb unwanted vibration for clearer mid and high frequencies. The neckband design of the ATH-CKR55BT conveniently situates the in-line mic and controls for easy access and places the battery case on the upper back where, if desired, it can be attached to your shirt collar with the included clip. Also included are four sizes (XS, S, M, L) of interchangeable ear tips, a 30 cm (11.8") USB charging cable, and a protective pouch. Features: - - Bluetooth wireless technology with in-line mic and controls for answering/ending calls, controlling music & video playback, and controlling volume on Bluetooth wireless devices - - Newly designed, compact 10.7 mm drivers deliver exceptional, full-range wireless audio - - Built-in amplifier for a sound field with enhanced depth and improved resolution across the frequency range - - The internal lithium polymer battery provides seven hours of continuous use (200 hours on standby) on a full charge - - Includes silicone eartips (XS/S/M/L), secure-fit clip, 30 cm (11.8") USB charging cable, and protective pouch - - The compact housings are designed to provide a comfortable fit for ears of all sizes - - Machined brass stabilizers absorb unwanted vibration for clearer mid and high frequencies - - Compatible with aptX and AAC codecs for high-quality sound and low latency - The included clip lets you attach the battery case to the back of your shirt collar Specifications:  Type Dynamic Driver Diameter 10.7 mm Frequency Response 5 – 35,000 Hz Sensitivity 103 dB/mW Impedance 16 ohms Battery DC 3.7 V lithium polymer rechargeable battery Battery Life 7 hours of continuous use (200 hours standby) Charging Time: Approx. 3 hours Weight 17 g (0.6 oz) Accessories Included 1 x 30 cm (11.8") USB charging cable, 1 x ear tips (XS/S/M/L), 1 x secure-fit battery clip, 1 x protective pouch Type (Microphone) Condenser Sensitivity (Microphone) -44 dB (1V/Pa, 1 kHz) Frequency Response (Microphone) 100 - 10,000 Hz Polar Pattern (Microphone) Omnidirectional --------------------------------------------------------------- Communication System: Bluetooth Version 4.1 Support Codec: AAC, aptX 1 Year Warranty