Founded in Philadelphia in 1936, today, we are housed in our modern plant in suburban Trevose, Pennsylvania, where, after more than 65 years, our company remains family-owned and managed. 3 GenerationsGMP specializes in the CNC Machining and manufacturing of precision components and assemblies. Over the years, we have established a reputation for quality and reliability. GMP's OEM division designs, prototypes and manufactures tools and equipment for the telecommunications, power utility and cable television industries, as well as for the contractors who serve these industries.