Designed to Move - No limitsThese earphones will stay on your ears regardless of how extreme your activites, thanks to the Skull fit hanger function that ensures a secure and stable fit. By incorporating high performance 9mm speaker units the headphones guarantee powerful bass reproduction. Our new "Active fit" function adapts the nozzle to your ear shape resulting in an immersive listening experience wherever you take them.The headphones have a sweat-proof design and come with dual coiled cords that offer total wearing flexibility. The cords can be tied at the back of the neck for maximum freedom of movement.