Abstract: A transparent plastic mark locator for determining compliance of indicia with postal specifications. The locator is a rectangular transparent plate with three perpendicular locating edges. Indicia on the plate define areas for location of postal specification information and codes including three alternative Facing Identification Mark patterns for use in a defined "FIM" print area.

Abstract: A machine wherein flat blanks are fed from a stack thereof to be folded and glued into envelopes. The machine is provided with an optical sensing device which is operable to sense when the stack of blanks diminishes to a predetermined height whereupon the machine will be turned off automatically so as to prevent a plurality of blanks from being simultaneously fed into the machine from the diminished stack to jam the machine. The machine operator can then add blanks to the stack and restart the machine. The sensing device can be turned off by the operator in order to run all of the blanks in the stack through the machine at the end of a blank run or at the end of a working day.