The colors red, gold and black are claimed as a feature of the mark.
The color red appears in the inner design of the keystone, the color gold appears in the outer design of the keystone and in the term "KEYSTONE," and the color black appears in the outlining of the keystone designs and in the wording.
"BUILT BY KEYSTONE MFG. CO., BOSTON, MASS., U.S.A."
The mark consists of a design in the shape of a keystone containing a smaller design in the shape of a keystone which itself contains the term "KEYSTONE". In the bottom and center between the two designs of the keystones and in smaller font is the term "BUILT BY KEYSTONE MFG. CO., BOSTON, MASS., U.S.A.".