We are selling $20 voip adapter with 2fxs :

* Functions :
Dialing Plan
Dialing Plan support
Status indicator
Web displays register status
Support local update
Support local update
Support remote update
Support remote update
Support remote configuration update
Support automatically remote configuration update
Auto new version check and upgrade
Router/ Bridge function
Default is router function
Support Tos/ Diff Serv
You can have a special tag on RTP and call signal packet
Caller number can be transport to phone
Caller number can be transport to phone, support FSK
Can adjust volume
Input gain and output volume can be adjust
Hot line
The terminal will auto dial out the number you preset when you pick up the phone.
Provide CPC signal
Provide polarity revise signal
Can work with the billing machine which support polarity revise signal
Can automatically reject anonymous incoming call
Can make a private call
Do not send your caller ID out
Inbound IP relay function
This function can let you put this device before/over your PABX and only use 1 account on all the FXS ports.
Advanced Features
Call hold
Call Transfer
Attendant transfer, Blind transfer
Call waiting
MWI
Support MWI information form softs witch
Do Not disturb
3-Way calling
Support 3-way calling
Call Forwarding
Includes offline call forwarding and online call forwarding. There are 3 types of online forwarding : No Answer, Busy and Always.