Owner's Marks
Maker’s marks for planes are always found on the toe of the plane rather than the heel. Klontz is a previous owner’s name rather than the manufacturer. These appear to be American planes and the standard reference for American woodies is A Guide to the Makers of American Wooden Planes by Emil and Martyl Pollak. Check the toe end of the plan and I imagine you will find the maker’s marks, although they aren’t always well struck and can be rather faint.
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