2B20YEAR is specifically constructed to resist tampering and vandalism. Whenever you have to specify exit signs for an explosive, corrosive, wet or other harsh environment, 2B20YEAR is the sign of choice
ILLUMINATION SOURCE: Borosilicate (hard) glass, internally coated with zinc sulfide phospor, and filled with tritium gas. No energy source required. BRIGHTNESS: Minimum initial brightness at time of manufacture of 0.15 foot lamberts. CONSTRUCTION: Encased in high-impact ABS fire-retardent plastic.
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