Sinclair Manufacturing Company was founded by John C. Sinclair in 1946. From a screw machine job shop, the company diversified into metal stampings and light assembly. Inspired by a new design for light sensitive relays, Sinclair began manufacturing hermetic glass-to-metal seals in the early 1960's.

Today, 70 years after opening its doors, Sinclair remains a family-owned business. The company continues to rely upon its traditional expertise in machining and toolmaking in order to produce hermetic packages to the highest possible standards, utilizing either glass or ceramic seals. Capabilities are continuously enhanced to ensure that Sinclair customers receive the quality and reliability they have come to expect.

Applications of the company's products routinely help fulfill aerospace, defense, medical and other high reliability component requirements.

Sinclair serves customers worldwide from it's 40,000 square foot manufacturing and administrative facility located in Chartley, Massachusetts - 35 miles south of Boston.