Self-Sealing Envelope Printing Catalog Envelopes Printing in China Regular Envelop Printing Window Envelope Printing 9X12cm size availableC4,C5,C6 ,DL,ZL or any other sizeenvelope closure methodlick seal,peel,sealmaterialoffset paper,white card paperstyleself-sealing envelope,catalogue envelope,regular,window envelope An envelopes a packaging product, usually made of flat material such as paper ...