Gentex GEC3-24WR 24VDC Selectable Candela Low Profile Evacuation Horn & Strobe - Red Faceplate Prewire Entire System, Then Install Your Signals Ease of Supervision Testing (Super-Slide) Checkmate Feature: Instant Voltage Verifiication Lower Installation and Operating Costs Input Terminals 12 to 18 AWG Switch Selection for High or Low dBA Switch Selection for High or Low Frequency (1500-3000Hz) Switch for Temporal 3, Chime, or Whoop Tones Tamperproof Re-entrant Grill Surface Mount with the GSB (Gentex Surface Mount Box) Synchronize Strobe and/or Horn by Using Gentex Synchronization Module