What can I say. These envelopes are great. The adhesive gum sticks and keeps the invoice inside all the way through the mail to the client. They are the best window envelopes ever!
I needed no. 10 window envelopes. They were not available. Next time I will go to Office Depot. I use these envelopes for invoices. The invoices do fit in the no. 9 envelopes but just barely.