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The Padlock Patent Archive

Three centuries of keeping things shut

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Mail-sack lock

Patent drawing sheet showing ten figures of a padlock design, including exterior side views, internal mechanism with levers, catches, and springs, individual component plates, a locking-bar assembly, and a specially shaped key with cut-away shank.

PADLOCKMartin H. Lutz and Morrow Moore · June 15, 1897

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