These are my favorite envelopes for mailing oversized 8-1/2 x 11 plus documents. The envelopes are sturdy and don't tear during shipping and they hide the contents.
I use this to mail information to my prospective clients. Myoolder accontnts rema undamaged because the per is pretty sturdy. It is nice that the contents cannot be seen through the envelope to keep a neat appearance. The gummed flap is a better option than peal and seal since it does hold very well.