Alpha Green Enjoy up to 8 hours of listening with these Jaybird X3 wireless earphones. Their Bluetooth connectivity syncs with the MySound app to create custom sound profiles, and they're sweat-proof for use during intense workouts. These Jaybird X3 wireless earphones are 34 percent smaller than the previous X2 model for comfort even under a helmet. In-ear design Fits securely and directs music into your ears for full, uninterrupted audio. Bluetooth 4.1 interface Enables simple wireless pairing with your Bluetooth-enabled device. Supports HFP, HSP, SPP, A2DP and AVRCP Bluetooth profiles. Noise isolation Helps minimize background sounds. The Jaybird MySound app gives you full control of your X3 sound profile. Personalize your sound settings and have them stored on your earbuds for use with any music device. Rechargeable battery Offers up to 8 hours of use on a charge. In-line microphone Lets you enjoy hands-free calls. Sweat-resistant Provides protection from sweat, so you can easily wear headphones while working out. 5.8mm drivers Deliver powerful sound. 20Hz - 20kHz frequency response For faithful sound reproduction. 16 ohms impedance To efficiently conduct power. 103dB sensitivity Provides powerful audio. Stereo design Delivers crisp tones. Carrying pouch included For easy portability. Clothing clip Keeps the headphones in place as you move.