Orbit ESSE-B-2-R-AC LED Surface Edgelit Exit Sign, Black Casing, 2 Face, Red Letters, AC Only Choose Pack:4 Pack which just means they work

which just means they work in various setups

Optimal Power Handling: With an amperage rating of 40A

patent pending mechanical design stringently tested to conform to UL263 and ASTM STD E119 to provide protection against the spread of heat and flames into the ceiling cavity for 1 hour and 2 hours

Easy Installation: Multiple knockouts for flexible conduit entry

Powerful Performance: 3-phase 4-wire system with a dual voltage rating of 120/240V or 120/208V (225A)

Orbit ESSE-B-2-R-AC LED Surface Edgelit Exit Sign, Black Casing, 2 Face, Red Letters, AC Only Choose Pack:4 Pack which just means they workCategory Exit Signs Page J11 Features: Dual Voltage Input 120 277VAC Operation UL Listed for Damp Location Long lasting, Energy Saving LED Lamps 90 Minutes Minimum Emergency Operation (EB Only) Premium Grade Extruded Aluminum Housing Aluminum Canopy for wall, ceiling or end mounting included Field applied Chevrons Included UV Stabilized ultra clear acrylic Edge Lit Panel Mirror divider on double face versions Single Face Panels are Clear, Double Face