Aptly named Communications Systems makes connectors and wiring systems for telecommunications networks. The company operates through subsidiaries. Its Suttle and Austin Taylor units make connectors, adapters, and other devices for voice, data, and video communications. Transition Networks makes converters that move data between copper wire and fiber-optic networks, LAN switches, and print servers. JDL Technologies provides schools and businesses with telecom network development services and software. Communications Systems sells directly and through distributors. Major customers include AT&T (accounting for 9% of sales) and Verizon (6% of sales).