"Sports-type headphones" leaving ears free to hear outside sounds and enjoy music while running safely. Speakers use newly developed "bone conduction drivers" to directly feed sound without using the ears. "Super-lightweight design" at only 28 g makes running perfect. Semi-waterproof design for rain or sweat makes running perfect. "Reflection sheets" on front and rear sides are lit up by car headlights for the user's safety. "Back-band type" = minimal impact on hairstyle. Three colors matching running wear.