With limited options on short notice these envelopes fit my needs for mailing 28-32 page booklets (regional newsletter). Sturdy yet flexible. However when mailing dozens of copies I would have preferred self-sealing envelopes for faster throughput.
A large percentage of these envelopes need to be taped on the sides because the glue was no good. Not great for mailing if someone isn't paying close attention as they'll get caught in the mail machines (speaking from experience)
I'm glad to have these now in place of business envelopes where i had to white out an address. they are a bit smallish for more than 20 pages of text but suit most purposes for multiple page letters or documents.