Mac Papers Envelope Converters (MPEC) is a leading U.S. envelope manufacturer offering cutting-edge technology, quality and unsurpassed expertise. With an annual production capability of over 3.8 billion envelopes, MPEC is proud of its excellent customer service, dedicated people, award-winning flexography and 99% on-time delivery rate. Our sister company, Mac Papers, is one of the largest wholesale distributors in the Southeastern U.S., recognized as a leading partner for paper and print, wide format and graphics, packaging, facility supplies and office products.