Quad Band 1 Gateway 1 Channel GSM Voip Goip Voip Converter SIP Ip PBX Phone Adapter DBL Quad Band 1 Gateway 1 channel GSM VoIP GoIP VoIP Converter SIP IP PBX Phone Adapter DBL Warranty 1 year. Return policy. Returns accepted within: 14 Days. Refund given as: Money Back. Return postage paid by: Buyer.