These Quality Park 9 x 12 kraft envelopes have speedy self seal closures; press it, seal it and fly through your daily mail routine; box of 250 Redi-Seal envelopes have 2 adhesive sides; press closed for a clean, sanitary seal without envelope moisteners or clingy strips; no water, no waste Heavyweight 28 lb kraft paper envelopes are opaque to protect private contents; strong enough for shipping, sorting or organizing tasks Inkjet printer compatible and perfect for use with address labels; not recommended for the laser printer A great value; large envelopes are an economical way to send manuscripts, certificates or other documents you’d rather mail flat