McGrath RentCorp is a business-to-business rental company operating in the United States and internationally. It rents and sells relocatable modular buildings, portable storage containers, and electronic test equipment through four segments: Mobile Modular, Portable Storage, TRS-RenTelco, and Enviroplex. Mobile Modular provides modular buildings for uses such as classrooms, temporary offices, sales offices, construction field offices, restroom buildings, health care clinics, childcare facilities, and office spaces. Portable Storage offers steel containers for temporary storage to construction, retail, commercial and industrial, energy and petrochemical, manufacturing, education, and healthcare markets. TRS-RenTelco rents and sells general purpose electronic test equipment, including oscilloscopes, amplifiers, analyzers, signal source, and power source test equipment, primarily for aerospace, defense, electronics, industrial, research, and semiconductor industries, as well as communications test equipment for fiber, copper, and wireless networks. Enviroplex manufactures and sells portable classrooms directly to public school districts and other educational institutions in California. The company was incorporated in 1979 and is based in Livermore, California.