Nice white 28lb. paper envelopes with the flap opening on the long side and seamed at the end/edges. I bought these envelopes for the purpose of storing documents, brochures, 8 x 10 photos, etc... mainly in hanging files. I like them better than plain manila folders (open or closed end). They offer ample room for several pages and would work well as mailers (documents/photos/etc...). You also avoid any issues with the USPS by using envelopes without metal clasps. I can't speak to the quality of the glue used on the flap. I would probably used tape as insurance. These envelopes were just what I wanted and at a fair price.