Federal Envelope, based in Bensenville, Ill., is a family-owned business and is a custom envelope manufacturer. Established in 1965, it produces three types of envelopes, diagonal seam, open-side and open-end envelopes. It manufactures all variations of these three types of envelopes, in up to six colors, for printing by flexo, litho and jet process. Its Web site gives customers detailed specifications of its prepress requirements. Most envelopes would fall under one of these three types, including bangtails, Z-fold bangtails, wallets, remittance, booklets and baronials. Federal Envelope s combined capacity for all types of envelopes is more than 200 million per month.