Physical description
A device of 7 rings made by "Trugrade". Circa 1930s.
Inscriptions & markings
Graduation from 2 inches up to 3 inches, by 1/8 inch.
A device of 7 rings made by "Trugrade". Circa 1930s.
Graduation from 2 inches up to 3 inches, by 1/8 inch.