Our company uses this product to send out our account payables. We are rest assured the billing gets to our customers in a secure way. We have never had any problems with these clasp envelopes.
This envelope can be used when you want to mail several pieces of mail to someone who no longer lives at your address. The extra 1/2 inch is enough to include standard #10 envelopes.
We are doing a mass mailing which includes 5 forms and a SASE business size which is 9 1/2 inches long also. Everything fit and we were able to do our mailing easily.
The USPS changed the classification of letters and large envelope rates a few years ago. Staples sells a 6x9 and 6 1/2 x9 1/2 kraft envelope. Staples should have a note or label on the packaging that tells the consumer which qualifies for the letter rate. Naturally I bought the 6 1/2 for the extra space and it DOES NOT qualify for the letter rate. I paid a higher price for these envelopes that are smaller than the other much larger envelopes that require the same postage rate.
I discovered too late that using 6 1/2" X 9 1/2" rather than 6"X9" envelopes cost an extra $44.00 to mail a newsletter!! A disclaimer on the box indicating postal rate for large envelope would be helpful.