This antique brass pressure gauge was manufactured by U.S. Gauge Co. in Worcester Massachusetts around 1910. US Gauge Co. filed for the patent on Sep.18 1906.It features the logo of Rockwood Sprinkler Co. and was used for measuring pressure in water systems. The gauge is in good working condition and has a beautiful patina that adds to its vintage charm. It would make a great addition to any collection of antique tools or plumbing equipment. It also would make a great decorator piece for that steampunk look in your loft or apartment. Thanks for your interest in this piece.