About Product:Transmission range: 10 meters function: support music, voice control, phone, electricity, according to a multipoint connection processing custom: no printing LOGO: can be bluetooth protocol: 4.2 track: stereo way of use: whether wearing type single and double ears: bilateral stereo applicable gift-giving occasions: opening ceremony, birthday, awards ceremony, wedding, advertising promotions, business gifts, anniversary celebrations, public relations planning, fairs, festivals, employee benefits, housewarming colors: green, red, white, black, blue