Description 1 With one button you could turn on off the device pick up the phone or hang up the phone play or pause the music 2 You could answer the phone by picking up the earphone and hang up the phone by putting it in the charging base 3 Overcharge protection 4 You could worn it in the wrist or put it in the key ring Specification Size21 8x21 8x25mmStandby time48 hoursHolding time1 5 hoursHolding distanceWithin 15 meters bluetooth range4 1 metersOutput voltage9 30V DCInput current5V 2 1A Package Included 1 X Car Charger