Description COMSYS Holdings provides a wide range of engineering and infrastructure development services for the telecommunications, electronic supply, and information technology industries. Services include cable tunnel construction, optical fiber installation, and base station construction for wireless networks. The company's largest customers are leading Japanese communications service providers NTT and NTT DoCoMo. COMSYS Holdings Corporation was established in 2003 as a joint holding company of Nippon COMSYS Corporation, SANWA ELEC Co., and TOSYS Corporation.