Joe O'Brien (Dublin Fingal, Green Party) | Oireachtas source

One is a landline alarm, which is installed when the participant has a standard telephone line. The second option is a broadband alarm, which is installed when the participant has a broadband line. The third alarm is the GSM version, which is installed when the participant does not have a standard telephone or a broadband line. This latter unit works off the mobile phone as well.

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