these double-sided photoluminescent aluminum signs absorb and store energy from ambient fluorescent light. Signs are easily visible in the event of a sudden blackout. Signs are ul924-listed by etl – intertek testing. Non-electrical, non-radioactive signs are maintenance free; no mechanical or electrical power source required and will last 25+ years. Meet nfpa 101 – life safety code, jcaho and osha requirements. Meet current building codes including ibc, ifc, icbo, boca, sbcci and nfpa. Leed qualifier. 50-foot viewing distance. Each sign comes with four chevrons inside the package that installer inserts into the aluminum frame on-site if directional indication to the left and/or right is needed. Easy do-it-yourself installation = no electrician needed. Double-sided sign comes with 1.5-inch bracket (item-no.: 600055) included, which is suited for ceiling and flag/ side-wall mount. For extended ceiling mount, select from either 10-inch ceiling mounting bracket (item-no.: 600056) or 19.5-inch ceiling mounting bracket (item-no.: 600057).