Yeastar EX30 Expansion Board w/ E1/T1/PRI Port
1 E1/T1 Port Expansion Board for Yeastar P560 / P570 / S100/ S300 systems
Description
Yeastar EX30 Expansion Board w/ E1/T1/PRI Port
[embedyt] https://www.youtube.com/watch?v=igh4wSD8IRE[/embedyt] 
