Folder Sealers
Paper folder sealers are used to fold special pressure sensitive paper. As the paper is folded, pressure rollers roll along the edge of the paper, bursting open tiny glue pockets that seal the letter shut. Pressure sealed documents are typically opened by tearing off a perforated side or tearing open the sealed portion of the letter. Documents that have been folded and sealed do not require an envelope for mailing and are often used for mailing bills, invoices and other mailed documents.
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