The Grandstream GXW4502 is a one port VoIP Digital gateway supports up to 60 concurrent calls. The GXW4502 offer PRI/ E1/T1 Line add-on capability to IP Telephone Systems in a cost-effective way. The GXW4502 Digital Gateway features two PRI/ E1/T1 Line. This VoIP Gateway supports a wide range of voice codecs such as G.722, G.729, iLBC, and more. The digital Lines are software configurable and support PRI, SS7, MFC R2.The Grandstream GXW4502 having two inbuilt PRI/ E1/T1 Port and capable to handle 60 concurrent calls. This VoIP gateway ensures amazing audio quality with carrier-grade Line Echo Cancellation [ 128ms-tail-length].