#9 Double Window Security Envelopes, HERKKA No.9 Double Window Business Envelopes Designed for Quickbooks Invoices and Business Statements - Number 9 Size 3 7/8 Inch X 8 7/8 Inch - 24 LB - 500 Pack

Quality product, secure, adhesive works fine, much less expensive than big box store. Purchased these because the local store doesn’t keep #9 size in stock. No issues at all and will purchase in the future.

The envelopes work perfect for sending business invoices. The adhesion is good and envelope is well made.

These are our go to envelopes for work and they are the best quality and price.

I mail bills for our business each month and these envelopes are a great value for the money. The peel strip takes a little tugging but nothing I can't handle consider the money I saved.

Not bad quality but not great quantity either. Envelopes are slightly thinner material than the Amazon brand I used to purchase were. Closure stays closed and envelopes don’t tear open. You cannot see through envelope when statements are placed in which is good. They work for end of the month statements and I will purchase again as they’re self closing.

Nice to not have to lick to stick the envelope shut. These are less expensive than others I’ve purchased from the office chain stores and seem to be of a higher quality.

These envelopes are a good quality. I especially liked the stickiness of the seals. I have used other brands before and the seals did not hold and I would have to add tape to make sure my checks made it through the mail. I will definitely order again!

Just a good standard double window envelope for quick books style invoices. Nothing fancy just easy to use.