The "M" stands for mixed mail (letters and flat envelopes). Patented feeder technology allows smooth operations over a variety of mail types. This unit includes real-time scanning, printing and sorting capabilities. The model "M" can be configured with up to 256 bins. As in all Tritek multi-bin machines, sorting schemes are completely user-configurable. Tritek's advanced OCR and mail processing software is custom designed for the automation of the mixed mail stream.