C-Tec Sigtel Sigtel Master Controller Ideal for disabled refuge, fire telephone and stadium marshalling application. Allows operators to communicate with up to four disabled refuge or fire telephone outstations. Expandable to 12 lines using an ECU-8 expansion unit. Networking facility allows up to four controllers to be interlinked allowing systems of up to 64 lines to be implemented. Easily interfaced to NC951 accessible toilet alarms, PDA audio-frequency induction loop systems, strobes, CCTV activation relays, etc.