1-FXS Port Analog Telephone Adapter Google Voice pre-configured (make and receive free calls in US and Canada using Google Voice) Google Voice Pre-configured Open adapter - you can use it with any other VoIP provider Support Voice Codec: G.711(a/?law), iLBC, G.723, G.729A/B, G.726-32, T.38(fax) 1 FXS, 1 Ethernet port