A printer includes a printing section configured to perform printing on roll paper, a transport surface (hot plate) where the roll paper on which printing has been performed is transported, and a heater unit (heater) for heating the transport surface. The stated transport surface includes a plurality of projections with which the roll paper makes slide contact.

A stacker device in an items processing system is a last station of a mail line. The stacker device has a receiving plate to receive flat items, a longitudinal alignment wall, graduated in at least two steps, at a rear side of the stacker device, and a stop wall that is arranged at the downstream end of the receiving plate.

A paper sheet storage device includes: a storage that stores a paper sheet inclined with respect to a horizontal direction in a storage space narrower than the paper sheet in width; and a guide portion that guides the paper sheet so as to cause the paper sheet to freely fall in the storage space such that all sides of the paper sheet are inclined at an angle different from the horizontal direction.