The second set of N/O or N/C contacts in a THERMOFLEX™ heat detector is used to activate a local ancillary function that includes elevator recall, release of magnetically-held doors, local signal operation, local annunciation, etc. In many cases this set of contacts will be connected to a controlling relay that is used to switch heavier voltages. The model number suffix “-2”, indicates that the detectoir is a double circuit with two (2) sets of Normally Open (N/O) contacts. The model number suffix “-2C”, indicates that the detectoir is a double circuit with two (2) sets of Normally Closed (N/C) contacts.