... 80 GSM Internal opaquing non-opaque Seams: Inside Window/plain: Window Professional manufactuer of commercial envelope, business envelope, gift ... envelope, wallet envelope, pocket envelope, window envelope, gummed envelope, peel and seal envelope Stock size: C7, c6, c5, c4, ... dl, 150x150, 145x145, 130x130, #10, mini Customer size and sample processing are welcome Competitive price and fast delivery