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Box of 500 white #11 envelopes with poly window diagonal seam vellum finish

WESTERN STATES

WESTERN STATES #11 Poly Window Envelope 4.5 x 10.375 24# White Diagonal Seam 500/Box

SKU CH-5FC0-0M363

Box of 500 white #11 poly-window envelopes, 4.5 x 10.375 inches, 24 lb SFI-certified sulphite with diagonal seam and vellum finish

  • SFI certified paper supports responsible forestry
  • 92% brightness gives crisp document presentation
  • Poly window protects contents while showing address
  • Diagonal seam construction adds strength for mailing
  • 500 envelopes per box supplies high-volume needs

#11 Poly Window Envelope

The #11 poly window envelope measures 4.5 by 10.375 inches and uses 24 lb white sulphite paper with a vellum finish. It is SFI certified and features a diagonal seam construction with a remoistening seal. The box contains 500 envelopes suited for daily business mailing.

Replaces standard closed-face envelopes

This envelope replaces closed-face versions when the recipient address must show through a transparent window. The jump is worth it for high-volume statement or invoice runs where hand-addressing each piece would slow the mailing process.

Holds folded letter sheets

The A-style window sits 1-1/8 by 4-3/4 inches, positioned three-quarters of an inch from the left and half an inch from the bottom to align with common folded letter formats. A single carton holds 2500 envelopes for extended supply. Buyers needing non-window security envelopes or larger catalog sizes should look elsewhere.

Highlights

  • SFI certified paper supports responsible forestry
  • 92% brightness gives crisp document presentation
  • Poly window protects contents while showing address
  • Diagonal seam construction adds strength for mailing
  • 500 envelopes per box supplies high-volume needs

Specifications

BrandThe Envelope Supplies Shop

Questions about this item

What are the exact envelope dimensions and window placement for the #11 size?

The envelope measures 4.5 by 10.375 inches with a poly window sized 1-1/8 by 4-3/4 inches positioned 3/4 inch from the left edge and 1/2 inch from the bottom.

How do I seal these diagonal seam envelopes correctly without tearing the flap?

Moisten the remoistening seal on the flap down closure evenly across the full width, press firmly for several seconds, and avoid over-wetting which can weaken the 24 lb sulphite paper.

When should I replace the box based on paper brightness degradation?

The SFI certified white sulphite stock maintains 92% brightness indefinitely in the sealed box; replace only if envelopes show yellowing, moisture damage, or the poly window clouds from improper storage.

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