This vintage Marsh gauge, Model no. PG-73 rated form 0 to 400 psi, stands out as a fascinating piece of industrial history. Manufactured by the Marsh Instruments Company, it features a robust Safe-case design with an outer casing made of Bakelite. Bakelite, an early form of plastic invented in 1909, became widely used by the 1920s and remained a staple material through the mid-20th century, before being largely replaced by more modern plastics after the 1950s. While the exact date of this particular gauge’s production is not specified, it’s likely it was made sometime between 1920 and 1950, given its materials and design. Though it is missing its glass cover, the retainer ring remains intact, preserving the gauge's structural integrity.

The following applies to this product
	AD-2				CD-2	CD-3
		MD-5		SD-1	SD-2	SD-3		SD-5	WSR-1