Found some history for you...... would appear its circa WWI....
In 1912, Goodell-Pratt acquired the Stratton Level Company, a well-known manufacturer of carpenter’s and machinist’s levels located in a small factory at 26 School Street in Greenfield. A local fixture since 1869, the company had been founded as Stratton Brothers by Edwin A. and Charles M. Stratton, onetime building contractors who wanted to exploit their patent for adding brass strips to the edges of wooden levels to protect them from dings and chips. The levels were a success, and one of the operation’s best customers would turn out to be the Millers Falls Company. Millers Falls catalogs featured Stratton wooden levels from 1878 until almost 1890. The levels would reappear in the catalog in the mid-1890s after the Millers Falls Company’s attempts to manufacture its own wooden levels came to naught. A third brother, Oscar G. Stratton, worked for the firm although it does not appear that he became a partner. When Charles died in 1893, the name Stratton Brothers was retained.
Edwin Stratton’s son-in-law, the company’s production supervisor, Roland O. Stetson, bought the business in 1902. O. L. Richtmyre became the operation’s new president, and Stetson remained in charge of production. Stetson continued the Stratton tradition of manufacturing high-quality wooden levels but expanded the line to include moderately priced models as well. In 1908, after a brief attempt to re-brand the business as R. O. Stetson, the operation was incorporated as the Stratton Level Company. The Goodell-Pratt Company bought the business in 1912 and moved production to the second floor of its Greenfield plant shortly afterward. Roland O. Stetson became a Goodell-Pratt employee. The acquisition of the Stratton Level Company brought a well-respected line of wooden levels to Goodell-Pratt