Zen will endeavour to connect 999/112 Emergency calls across our Voice network, but we cannot guarantee that they will be connected and we recommend that emergency calls are routed over the PSTN, thereby ensuring that these calls have the highest chance of connecting possible. Numbers starting 1 and 09 are NOT carried by Zen Broadband Voice. To enable calls to 999/112 and number beginning 1 and 09 to be routed over the PSTN you are advised to purchase a Zen recommended Thomson TG784. This device provides a connection for your PSTN line thereby allowing such calls to be made via your existing telecom provider. UK landlines with an 01, 02 or 03 prefix, mobile telephone numbers, International numbers, non-geographic local and national numbers are carried by Zen Broadband Voice. Zen Broadband Voice calls count towards ADSL usage allowance. If you reach your ADSL cap, all calls will be routed over the PSTN and you will need to pay all charges to your current telecoms supplier. In order to sign-up to Zen Broadband Voice you will be required to pay via direct debit for all recurring services that you have with Zen Internet, though your first months' service payment can be paid by credit or debit card (This only applies to Non credit account customers). Zen Internet can not guarantee service compatibility with third-party hardware devices that haven’t been purchased from, or configured by, Zen Internet.