he emergency door release unit will only be used during an emergency evacuationbut should always be installed in addition to a standard door release button. In an emergency use of the standard door release button can impede evacuation flow as power to the lock release is only removed temporarily. Activation of the EVEBG will ensure power is permanently removed from the electronic locking system until re-set . Elite Security Products Surface mounting box supplied. Semi-flush mountable using standard one gang flush box. Re-settable ( no need for replacement glass ). Clear indication of activation. Key test facility. IP24 rated. Plug in terminal blocks for ease of wiring.