McGrath RentCorp is a company that provides business-to-business rental services. It operates through four segments: Mobile Modular, Portable Storage, Electronic Test Equipment Rental (TRS-RenTelco), and Enviroplex. The Mobile Modular segment offers modulars for use as classrooms, restroom buildings, health care clinics, sales offices, etc. The Portable Storage segment specializes in office and storage containers. The TRS-RenTelco segment rents and sells electronic test equipment. The Enviroplex segment manufactures portable classrooms for public school districts and other educational institutions.