This parallel drafting tool measures 12 inches long and 2 and half inches wide when closed. . It’s a solid tool in good working order as shown in the photographs. The only distinguishing mark is ESCO written on the cross pieces.
ESCO was founded in 1913 by Oregon businessman Charles (C.F.) Swigert as a local source of steel castings. The ESCO trademark was first used in 1926 and eventually became the company's new name.