Flexible design fits comfortably and stays put for all levels of exercise with easy on-ear controls for calls and music. Sweat proof and waterproof: Protected by a P2i Nano-coating, these headphones deliver sweat proof durability and meet the IP57 rating for withstanding fresh water up to one meter for 30 minutes. Quick Charge Technology: Powers a week of workouts with up to eight hours of listening time and a 15 minute quick charge can power up to a full hour of listening. Heart-pumping bass: Powerful speakers and custom codec deliver the heart-pumping bass and crisp highs of your music and only pause to let you take a call. Wireless updates: Get the latest firmware improvements sent directly to your headphones from the free Plantronics Backbeat FIT Companion app.