FAQ What is the address of DUPLEX? The address of DUPLEX is located at Rue du Centre 136, 1025 St-Sulpice. You can easily access it by public transport or car. What languages are spoken by DUPLEX? DUPLEX speaks Français. What is the phone number of DUPLEX? The phone number of DUPLEX is 021 691 06 06. You can reach us during opening hours for any information. What is the email address of DUPLEX? You can contact DUPLEX by email at the following address: client@duplex-id.ch. We usually respond within 24 hours.