Although Testek Inc. was founded in 1969, its history can be traced back to 1913.

George L. Nankervis Company was started in Detroit, Michigan in the early 1940s. George L. Nankervis Company was a major Test Stand supplier for the aerospace industry, a pioneer in designing and building Test Stands in the early days of jet engine development and production.

Cox Instruments founded in 1913, was a manufacturer of flow meters in Detroit, Michigan. Cox Instruments supplied fluid (air, fuel, oil, etc.) flow meters with the best accuracy in the industry. Cox also manufactured Fuel Test Stands. In 1950, George L. Nankervis Company and Cox Instruments merged and became known as Cox Instruments. This joint company continued as Cox Instruments and became a major supplier of aerospace and automotive Test Stands.

On the historic date of July 20, 1969, Neil Armstrong was the first man to walk on the moon. The same day, well-respected, key engineers from Cox Instruments founded Testek. By 1975, Testek was established as a major supplier for automotive and military aircraft test equipment.

In 1976, Testek acquired the manufacturing rights and the name of American Avitron. American Avitron was a major Test Stand supplier for the commercial airlines market worldwide.

During 1980, Cox Instruments Test Stand Group merged with Testek. Cox Instruments flow meter group became a separate group.

In 2009, Testek Inc, purchased the manufacturing rights and propriety data of AAI Mississippi formerly known as AAI \ ACL Technologies and ACL FILCO.

Just recently, in 2012, Testek Inc, became the Textron Systems licensed supplier for Textron Systems – Massachusetts and HR Textron test equipment.

Thus, Testek is proud to have the capability to design, manufacture, support and service Test Stands since 1913 (under George L. Nankervis, Cox Instruments, American Avitron, AAI ACL Technologies (ACL FILCO), Textron Systems Massachusetts, HR Textron and Testek Inc).