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Long lasting supply; ideal for everyday business use and professional mass mailings, each box of these premium #9 Security Envelopes provide a super long lasting 500 envelope supply, for the best value on the market! Click the Orange Button to order now.
Double windows; professional, advertising campaigns and many more, each envelope contains two front windows, easily read double front windows suitable for standard business and legal mailings, eliminating constantly printing and hand writing addresses, a 1-3/16" X 3-1/2" top window positioned 3/8" from the left and 2" from the bottom and the bottom 1" X 4" window is 3/8" from the left and 1/2" from the bottom.

Maintains professional look and feel throughout transit with our durable 24 LB white wove envelope paper. Save time with easy to use flip and seal self-seal design; With no need for licking or moistening, our self seal design allows for sending hundreds of invoices quickly and easily and is guaranteed to stay sealed with no need for tape or glue sticks.

Double window design: only sender and return address will show on your QuickBooks invoices and monthly bills through our unique 2 window.
Long lasting supply: large sized envelopes and 500 envelopes in every pack for a long lasting supply, perfect for everyday business correspondence and large mailing tasks! Click the Orange Button to order now. Quick-seal closure: our #9 envelopes are designed with an ultra strong SELF-SEAL adhesive strip to create a full, super secure seal across each envelope's width that won't easily open or tear, ideal for mailing for any letter sized and larger documents without splitting. No show of memo, Payee line or amount in windows.

These boxes of 500 white #9 double window security envelopes 3 7/8 in x 8 7/8 in protect your customers' sensitive data; a reflex blue pattern obscures the details of what's inside. 9 mailing envelopes measure 3 7/8 in height x 8 7/8 in width and are made of 24 lb white wove paper with professional side seams; #9 envelopes fit into #10 envelopes.



Provides complete business mail security: your invoices and statements will be completely hidden with our dark security tint design. Maintains professional look and feel throughout transit with our durable 24 LB white wove envelope paper.

Stock up on boxes of 500 window envelopes and save; great for bulk mailings, these number 9 envelopes show sender and receiver addresses and can be run through a postage machine. Protect critical documents or your customers' sensitive data; these tinted envelopes have a reflex blue pattern that obscures the details of what's inside.

1. Amazon Basics
#ad
500-Pack, Security Tinted, Double Window, Amazon Basics #9 Envelopes with Peel & Seal
#adAmazon Basics #ad - Double window allows sender and recipient addresses to show through. Interior security tint keeps content private; securely send checks, invoices, or other confidential documents.More information #ad
500-count pack of #9 security envelopes with Peel & Seal closure—no moisture needed. 24-pound white wove paper for quality and strength; ideal for home or office. Measures 3-7/8 by 8-7/8 inches each.Brand | Amazon Basics #ad |
Manufacturer | Amazon Basics #ad |
Height | 8.8 Inches |
Length | 1 Inches |
Weight | 5.96 Pounds |
Width | 3.88 Inches |
Part Number | amz43 |
Model | AMZ43 |
More information #ad
2. Aimoh
#ad
500 Count 30139, for Invoices, Statements & Documents, Security Tinted, Size 3-7/8 x 8-7/8-24 LB, 500#9 Double Window SELF Seal Security Envelopes
#adAimoh #ad - Quick seal adhesive; aimoh's #9 envelopes use ultra secure, super secure seal across each envelope’s width that won’t easily open or tear as with cheaper gummed seals, quick seal adhesive to create a full, perfect for larger and thicker documents. Security tint; forget thin, numbers and other data within, easily read envelopes these premium #9 Security Envelopes are designed with security tinted wave patterns which easily obscure details, perfect for mailing business statements and invoices while protecting sensitive information.Long lasting supply; ideal for everyday business use and professional mass mailings, each box of these premium #9 Security Envelopes provide a super long lasting 500 envelope supply, for the best value on the market! Click the Orange Button to order now.
More information #ad
9 double window quick seal security envelopes; tired of cheap thin, easily torn envelopes? Aimoh's#9 Security Envelopes are the perfect solution, extra large, with premium security tint, easily read dual front windows and super secure quick seal adhesive. Double windows; professional, advertising campaigns and many more, each envelope contains two front windows, easily read double front windows suitable for standard business and legal mailings, eliminating constantly printing and hand writing addresses, a 1-3/16" X 3-1/2" top window positioned 3/8" from the left and 2" from the bottom and the bottom 1" X 4" window is 3/8" from the left and 1/2" from the bottom.
Brand | Aimoh #ad |
Manufacturer | Aimoh #ad |
Height | 4.1 Inches |
Length | 11.5 Inches |
Weight | 0.01 Pounds |
Width | 9.2 Inches |
Part Number | FBA_30139 |
Model | 30139 |
More information #ad
3. Blue Summit Supplies
#ad
Designed for Quickbooks Invoices and Business Statements with Self Seal Flip Press and Seal Flap -Number 9 Size 3 7/8 Inch X 8 7/8 Inch, 500 No. 9 Flip and Seal Double Window Security Envelopes
#adBlue Summit Supplies #ad - Quickly and easily stuff our wide envelopes with several invoices or business statements. Provides complete business mail security: your invoices and statements will be completely hidden with our dark security tint design.Maintains professional look and feel throughout transit with our durable 24 LB white wove envelope paper. Save time with easy to use flip and seal self-seal design; With no need for licking or moistening, our self seal design allows for sending hundreds of invoices quickly and easily and is guaranteed to stay sealed with no need for tape or glue sticks.
More information #ad
Perfectly fits quickbooks invoices and business statements: sender and return address will be visible on your QuickBooks invoices and monthly bills through our unique double window design.Brand | Blue Summit Supplies #ad |
Manufacturer | Blue Summit Supplies #ad |
Weight | 5.27 Pounds |
Part Number | BSS-92588-007 |
Model | BSS-92588-007 |
More information #ad
4. HERKKA
#ad
HERKKA No.9 Double Window Bussiness Envelopes Designed for Quickbooks Invoices and Business Statements, 500 Count, #9 Double Window Security Envelopes, Number 9 Size 3 7/8 Inch X 8 7/8 Inch, 24 LB
#adHERKKA #ad - 500 pack self seal envelopes:herkka #9 security envelopes are designed with peel & seal closure—no moisture needed and a premium security tint to protect sensitive information and a super strong SELF-SEAL strip. Premium security check tint envelopes: the interior of our #9 Security envelopes use a dark navy, offer the protection contents and sensitive information, heavy coverage security tint to provide guaranteed privacy for your legal or business mail, a security tint makes envelopes hard to see through that ensures upmost privacy.Double window design: only sender and return address will show on your QuickBooks invoices and monthly bills through our unique 2 window.
More information #ad
Perfect for home or office; securely send checks or other confidential documents. Perfectly fits QuickBooks Invoices and business billing statements. Long lasting supply: large sized envelopes and 500 envelopes in every pack for a long lasting supply, perfect for everyday business correspondence and large mailing tasks! Click the Orange Button to order now. Quick-seal closure: our #9 envelopes are designed with an ultra strong SELF-SEAL adhesive strip to create a full, super secure seal across each envelope's width that won't easily open or tear, ideal for mailing for any letter sized and larger documents without splitting. No show of memo, Payee line or amount in windows.
Brand | HERKKA #ad |
Part Number | No9-2Win-Lixing |
More information #ad
5. Quality Park
#ad
Invoices/QuickBooks Statements, Quality Park #9 Security Envelopes, 3-7/8 x 8-7/8 Inches, Self Seal, Double Window, 24 lb White, 500/Box QUA24529
#adQuality Park #ad - Double window envelopes show sender and receiver addresses; top window is 1 3/16" x 3 1/2"; 3/8" from the left; 2" from the bottom; bottom window is 1" x 4"; 3/8" from the left; 1/2" from the bottom.These boxes of 500 white #9 double window security envelopes 3 7/8 in x 8 7/8 in protect your customers' sensitive data; a reflex blue pattern obscures the details of what's inside. 9 mailing envelopes measure 3 7/8 in height x 8 7/8 in width and are made of 24 lb white wove paper with professional side seams; #9 envelopes fit into #10 envelopes.
More information #ad
Stock up on boxes of 500 machinable #9 envelopes for bulk mailings. Redi-seal self seal mailing envelopes require no moisture; the unique double flap design allows you to simply raise the lower flap and press to seal.Brand | Quality Park #ad |
Manufacturer | Quality Park #ad |
Height | 3.63 Inches |
Length | 13.13 Inches |
Weight | 5.6 Pounds |
Width | 9.13 Inches |
Part Number | QUA24529 |
Model | QUA24529 |
More information #ad
6. Amazon Basics
#ad
White, 500 ct, Amazon Basics #9 Double Window Security Tinted Envelopes
#adAmazon Basics #ad - 9 envelopes measures 3-7/8 by 8-7/8 inches each. Ideal for 8. 5-by-11-inch computer-generated invoices and statements. 500 standard-size security-tinted #9 double window envelopes.More information #ad
Double windows 3/8-inch from the left to show sender info 2 inches from bottom and recipient info 1/2 inch from bottom.Brand | Amazon Basics #ad |
Manufacturer | Amazon Basics #ad |
Height | 0.01 Inches |
Length | 8.88 Inches |
Weight | 0.1 Pounds |
Width | 9.25 Inches |
Part Number | AMZ92W |
Model | AMZ92W |
More information #ad
7. Office Depot
#ad
Clean SealTM, Box of 250, 77166, White, Office Depot Double-Window Envelopes, 9 3 7/8in. x 8 7/8in.
#adOffice Depot #ad - Self-adhesive closure keeps the contents safely inside. Includes an office depot clean seal double-window envelopes #9 box of 250 Make mailing labels a thing of the past in your office with these Office Depot envelopes.More information #ad
Windows clearly display return and mailing address. Great for businesses that use check-writing software and computer-generated forms, double-window envelopes clearly display addresses from the inside. White double-window envelopes measure 3-7/8" x 8-7/8". Security tint inside provides confidentiality.Brand | Office Depot #ad |
Manufacturer | Office Depot #ad |
Length | 8.88 Inches |
Part Number | MPA/OD/156 |
More information #ad
8. Blue Summit Supplies
#ad
500 No. 9 Double Window Security Envelopes, Number 9 Size 3 7/8 Inch X 8 7/8 Inch, Designed for Quickbooks Invoices and Business Statements with Self Seal Peel and Seal Flap
#adBlue Summit Supplies #ad - Quickly and easily stuff our wide envelopes with several invoices or business statements. Our self seal design is quick and easy and is guaranteed to stay sealed with no need for tape or glue sticks.Provides complete business mail security: your invoices and statements will be completely hidden with our dark security tint design. Maintains professional look and feel throughout transit with our durable 24 LB white wove envelope paper.
More information #ad
Just peel and seal to create a strong lasting seal without licking or moistening. Perfectly fits quickbooks invoices and business billing statements: sender and return address will be visible on your QuickBooks invoices and monthly bills through our unique two window design.Brand | Blue Summit Supplies #ad |
Manufacturer | Blue Summit Supplies #ad |
Height | 4.5 Inches |
Length | 8.5 Inches |
Width | 12 Inches |
Part Number | BSS-92588-002 |
Model | BSS-92588-002 |
More information #ad
9. Columbian
#ad
Columbian #9 Double-Window Security Envelopes, 3-7/8 x 8-7/8 Inches, White, Peel & Seal, 500 per Box COLO166, for Invoices and Statements
#adColumbian #ad - Box of 500 columbian white double window #9 envelopes 3-7/8" x 8-7/8" with a SimplySafe tamper-evident seal and peel off Release & Seal closure; top window: 7/8" x 3 1/2"; bottom window: 1" x 4".Stock up on boxes of 500 window envelopes and save; great for bulk mailings, these number 9 envelopes show sender and receiver addresses and can be run through a postage machine. Protect critical documents or your customers' sensitive data; these tinted envelopes have a reflex blue pattern that obscures the details of what's inside.
More information #ad
Each #9 envelope is easy to open and close; simply remove the Release & Seal strip and press the flap closed for a clean, sanitary seal; use the pull strip to open without difficulty. Columbian #9 double window envelopes have a patented SimplySafe seal that will show signs of tampering, safeguarding against unauthorized opening.Brand | Columbian #ad |
Manufacturer | TOPS Products #ad |
Height | 3.75 Inches |
Length | 12.13 Inches |
Width | 9.13 Inches |
Part Number | COLO166 |
Model | COLO166 |
More information #ad
10. Office Depot
#ad
76169, Office Depot 100% Recycled Lift PressTM Double-Window Envelopes, Pack of 500, White, 9 3 7/8in. x 8 7/8in.
#adOffice Depot #ad - With office depot double-window recycled envelopes, there's no need to write out labels. Tamper-evident seal provides added protection. Windows display the return and mailing address. Office depot lift & Press white envelopes are security-tinted inside for privacy and confidentiality.More information #ad
Made of crisp 24-lb white wove for a substantial feel. Simply lift and press! lift & press closure provides a permanent seal immediately upon contact, so you can be sure that your documents will safely arrive at their destination. Plus, you can easily see addresses with these double-window envelopes.Brand | Office Depot #ad |
Manufacturer | Office Depot #ad |
Part Number | ODP76169 |
More information #ad