1x SHDSL 1x E1 ( PRA) 120 Ohm and 1x Nx64 ( V.35) . FlexDSL Standalone modem ( NTU) , 2x SHDSL ( TC-PAM 16, 23Mbps) , Master/ Slave, Multi-Service: 1xE1( PRA) 120 Ohm ( 75 Ohm BNC Possible) and 1x Nx64 ( V.35/ V.36/ x.21/ V.24) , accepts Local or Remote Power.