We have been using the invoice envelopes to send out letter and they cost is less that the #10 envelopes. I also am purchasing them online and with the free shipping it is costing me less money.
This is the best envelope I have found to use for our invoices. we have used them for a long time - my invoices fold just perfect to show our company name and the address as to where it needs to go. GREAT PRODUCT
For the most part these envelopes work wonderfully. However i've run across some in the box that the glue was not adequate to properly seal the envelope. That's the reason for the four stars and not five.
I have used these envelopes for years to mail clients invoicesand statements. They work great with Quickbooks printed invoices and statements. They also offer the security I need and require for my business. I would recommend these envelopes to any business wanting a good envelope at an affordable price.