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Box of 500 white 9 x 12 inch open side booklet envelopes with vellum finish and side seams

WESTERN STATES

WESTERN STATES 9 x 12 Open Side Booklet Envelopes 28# White Side Seams Box of 500

SKU CH-PXFN-YFKHN

White sulphite booklet envelopes, 9 by 12 inches, 28 lb stock, SFI certified, 500 per box

  • SFI certified paper supports responsible forestry
  • 92% brightness gives crisp contrast for printed text
  • Vellum finish provides a smooth professional feel
  • Side seam construction adds strength for bulky inserts
  • Box of 500 envelopes covers high-volume mailing needs

9 x 12 Open Side Booklet Envelopes

These envelopes measure nine by twelve inches and open on the long edge for easy document insertion. They suit offices, schools and mailrooms that send flat paperwork such as reports, brochures or catalogues. The box contains five hundred pieces for high-volume mailing. Buyers who need windowed envelopes or smaller sizes should look elsewhere.

28 lb White Sulphite with Vellum Finish

The 28 lb White Sulphite stock is SFI certified and offers ninety-two percent brightness for a clean, professional look. A vellum finish gives a smooth feel that feeds reliably through most printers and copiers. Side-seam construction keeps the flap flat for consistent sealing. No noise or thermal data applies to paper products.

Remoistening Seal and Side Seam Design

Each envelope uses a traditional remoistening seal that activates with moisture for a secure closure. Two side seams placed underneath provide structural strength while keeping the front surface uninterrupted for addressing or printing. A "Please Recycle" imprint appears on the back. The box weighs twenty-two pounds and ships as a single carton of five hundred envelopes.

Highlights

  • SFI certified paper supports responsible forestry
  • 92% brightness gives crisp contrast for printed text
  • Vellum finish provides a smooth professional feel
  • Side seam construction adds strength for bulky inserts
  • Box of 500 envelopes covers high-volume mailing needs

Specifications

BrandThe Envelope Supplies Shop

Questions about this item

How do you seal the remoistening flap on the 9 x 12 booklet envelopes without it sticking prematurely?

Moisten the adhesive strip only when ready to mail; keep the box closed in a dry area so humidity does not activate the seal early.

When will the remoistening adhesive on the 28# white sulphite envelopes lose its tack and need replacing?

The gum stays viable for years if stored cool and dry; replace the box once the flap no longer seals after moistening.

At what point does the 28# paper weight limit how many sheets can be mailed in a single 9 x 12 envelope?

The 28# stock handles typical multi-page inserts; bulk or heavy documents that exceed postal thickness rules will require a larger mailer.

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