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500#9 Single Window Security Envelopes, Thick Gummed Seal, Designed for Secure Mailing of Payroll Checks, QuickBooks Invoices, Return Mail, and Business Statements - 3 7/8 x 8 7/8

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$30.99

$ 15 .99 $15.99

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About this item

  • Perfect for mailing payroll checks, QuickBooks invoices, billing statements, confidential documents, and other business mail.
  • No need for tape or glue sticks as our strong gummed seal creates a hassle free and safe seal for all your sensitive documents.
  • Provides complete business mail security: your professional business mail will be completely hidden with our dark security tint design
  • Create professional looking mail with the added security of a single window envelope. Your business mail recipient address will show through the single window and you can quickly print your return address or add return address labels
  • Tamper proof design with our hot melt glue adhesive manufacturing process that allows the glue to penetrate the envelope, thus causing the envelope to tear if you open after sealing



Product Description

french bulldog with envelopes and white logo

#9 Business Envelopes with Security Tint and Secure Seal

A standard security envelope that’s ideal for everyday business use, our #9 mailer is made from durable 24lb white wove paper and keeps your documents safe and secure with a strong glue seal and dark security tint lining. This envelope is equipped with a low profile flap design, making it easy to fold and stuff up to 10 sheets of standard letter size paper inside with room for a #8 return envelope so your clients can quickly return payments. It can also be used as a return envelope itself when sent inside a #10 envelope, making the #9 one of our most versatile envelope choices, simple enough for everyday letters and statements, yet professional and secure enough for high-profile business communications.

Blue Summit Supplies Secure Seal Types

#10 envelope, self seal envelope

Peel & Seal!

Simply pull the backing off the envelope's flap to reveal an adhesive strip that can be folded over and pressed down to seal contents safely inside.

BSS-92588-013

Gummed!

Moisten the strip of adhesive found on the envelope's flap and fold over to seal contents securely inside.

BSS-92588-006

Flip & Seal!

No moisture is required, just flip up the bottom flap, fold over the top flap and press to secure contents safely inside.

blue summit supplies CMS 1500 envelopes

  • Secure Closure Types: Gummed, Flip & Seal, Peel & Seal
  • Industry Standard Durable 24lb White Wove Paper
  • Cross-Hatch Security Tint Keeps Contents Concealed

Compare Blue Summit Supplies #9 Business Envelopes

envelope comparison, #9

William Willett
2025-08-22 17:01:09
The value was good, I use these for members of my group to return their yearly renewal cards
aholic
2025-08-17 09:20:23
I use these at work for mailing out full sized company checks. These are easy to open, close, seal. Sturdy and secure, no seeing through the paper at all. I prefer the single window security envelopes, as my experience has been that two windows sometimes allow more of the face of the check to be seen and I prefer as much confidentiality as possible when mailing checks that are partially visible.I don't lick envelopes anymore, (sanitary/health cautions), and use a bottle of envelope moistener with adhesive in it and these stick super well without any corners lifting up.
MamaP
2025-08-07 10:28:45
Great value and a nice envelope. Fit QB checks.
Bailey
2025-06-26 17:42:04
The pork tab remains sticky as you peel it from the envelope and the glue sticks to your fingers
Brenda Garcia
2025-06-12 14:27:17
Great for basic business. Not super thick so you can still see through in the light. For everyday basics, this is the perfect inexpensive envelope.
All Season Lawn Landscaping
2025-06-10 17:27:46
Good quality
Jane Kirsch
2025-04-04 14:06:50
I use them to mail checks and they fit correctly.
Chris von Stein
2025-02-05 12:48:40
They looked fine, except the window on the envelopes I got were about 65% of the width, so I returned them. The picture here shows a window that is about 50% as wide as the envelope.
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