User Guide
Page 23
...It also introduces the ways you are provided with a robust firewall and content filtering. P-660HW-Tx v3 Series User's Guide 23 The P660HW-Tx v3 is an ADSL2+ router. Line commands are from the P-660HW-T1 v3 model. Note: All screens displayed in "3" denote a device that works over ISDN ...(Integrated Services Digital Network) or T-ISDN (UR-2). Models ending in this user's guide are mostly used for your ZyXEL Device...
...It also introduces the ways you are provided with a robust firewall and content filtering. P-660HW-Tx v3 Series User's Guide 23 The P660HW-Tx v3 is an ADSL2+ router. Line commands are from the P-660HW-T1 v3 model. Note: All screens displayed in "3" denote a device that works over ISDN ...(Integrated Services Digital Network) or T-ISDN (UR-2). Models ending in this user's guide are mostly used for your ZyXEL Device...