SUPERIOR SOUND, NO COMPROMISE: Powered by Sennheiser’s TrueResponse transducer, personalized with the built-in equalizer and with a wide range of Bluetooth codec support (AAC, aptX, SBC) ADAPTABLE ACOUSTICS: Open ear adapters for situational awareness so you can stay in tune with the world and closed ear adapters for passive noise cancellation to block distractions so you can focus on your workout SECURE CUSTOMIZED FIT: Compact, ergonomic design, interchangeable fins and a choice of ear adapters let you achieve optimal comfort and a secure fit IP54 DUST, SPLASH & SWEAT: Enjoy an outstanding audio experience no matter where you are or how much you push the limits LONG BATTERY LIFE: Get up to 27 hours of music playtime with on the go charging with the high quality case that comes with the product FULL DIGITAL CONTROL: Our Smart Control App for iOS / Android allows earbud functionalities to be personalized for your everyday needs; fully adaptable controls for music, calls and voice assistant, along with independent earbud use