Styled in Citron these SoundSport Wireless In-Ear Headphones from Bose can pair with up to two devices via Bluetooth, with or without the use of NFC tap technology. They also offer proprietary StayHear+ eartips that conform to your natural ear-shape for a more secure and comfortable fit. These features render them suitable for use during the most vigorous of exercise routines.Bose’s volume-optimized EQ ensures that the frequency response of these headphones stays balanced and even at any volume. With a sweat- and water-resistant construction conforming to the IPX4 industry standard in this regard they are engineered to survive the demands of your active life. Their lithium-ion battery is rechargeable via USB, and will provide up to six hours of continuous playing time.