About Product:Transmission range: 15 meters function: support music, phone, electricity, according to multipoint connection processing custom: is printed LOGO: can be bluetooth protocol: 4.1 track: stereo way of use: whether earplugs type single and double ears: unilateral hands-free applicable gift-giving occasions: birthday, awards ceremony, wedding, advertising promotions, business gifts, anniversary celebrations, public relations planning, festivals, fairs, employee benefits, housewarming colors: red, gold, grey, black whether cross-border supply of goods: no support for custom: support