Automatic mail sorting system coding grid - consists of five columns of ten digits with individual digits erased to make code

摘要

The coding grid is used to record a postal code on a mailing envelope for use with an automatic mail sorting system. The grid has five columns, each containing ten digits, with the column lines recording the numbers (1, 2...8, 9, 0) in succession. The required postal code is recorded by deleting one digit in each column. The coding grid may have reference markings (a, b) for correct positioning of the grid relative to one corner of the envelope. These markings may also be used for positioning of the recorded codes relative to the automatic code reader.