Grandstream GS-HT802 2 Port Telephone VOIP Adapter Selling because I have another one. This one has never been used. Price $60 (firm). The HT802 is a 2 port analog telephone adapter that allows users to create a high-quality IP telephony solution for residential and office environments. Its voice quality, advanced VoIP functionality, security protection and auto provisioning options enable users to take advantage of VoIP on analog phones and enables service provider s to offer high quality IP service.