Envelope and letter sign with word do not use as the headline

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Size: 5000px × 4200px
Photo credit: © Thanee Hengpattanapong / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: alert, banner, bill, break, breakdown, caution, disapply, disuse, downtime, envelope, equipment, error, facility, factory, guideline, headline, hold, icon, idle, ignore, industry, invalid, letter, machine, maintenance, neglect, notice, notification, operate, policy, prevention, prohibit, protection, reject, rule, sign, site, status, symbol, unavailable, utility, valid, vector, vectors, void, warning, word