The pressure seal system utilizes a pressure-activated adhesive on a single sheet of paper to create a mailer. There is no need for envelopes! Pressure seal checks elimate the costly steps of manual folding, stuffing, and sealing. Face printing includes a hidden ?void? pantograph in the center panel. This 8-1/2" x 11" form has a Z fold with green pantograph, microprinting, and blue stub. The back has thermochromic ink and a watermark. Sold in boxes of 2000.