Not a common patented chamfer guide, this set was sold by F. W. Slayton of Boston (so marked on the box), and is in the less common brass finish (also marked on the box), and is in the 1 ¼ inch size (also marked on the box). The green pasteboard box has a pink label. The brass guides have acquired a dark patina, but will buff up if any English ancestry wells up in you. The patent date, July 14, 1885 (Bastille Day, if your French blood rises) is marked on one of the guides. http://www.datamp.org/patents/displayPatent.php?pn=322040&id=12628. Fine.