... .Product Features 1,Modular structure,Analog ground for,Relay Access,Call Center,Branches of large companies,SME internal extension, many occasions;Two ... standards: G.711, G.723.1, G.729A Support hotline call, speed dial; Support T.38 fax, up to 14400bpsVariety of ... , you can switchboard ext; Support each other within the port call Support port forwarding, then rob, secondary dial, hotline FXO port ...