Filtronic plc designs, develops, manufactures, and sells radio frequency (RF) technology in the United Kingdom, Europe, the Americas, and internationally. Its products include E-band transceiver modules, power amplifiers, active diplexers, tower top amplifiers, and transmit and receive modules, along with custom waveguide diplexers, combiners, front end modules, GaN amplifiers, and microwave and millimeter wave transceiver products. The company also offers filter products such as ceramic, combline and interdigital, waveguide, custom, interference mitigation, lumped element, metal cavity, small cell, suspended substrate, and thin film filters, as well as switched filter banks, and provides hybrid manufacturing, plastic packaging, outsourced semiconductor assembly and test, electromechanical manufacturing, process engineering, RF design, and in-house testing services. It serves space, aerospace, defense, telecommunication infrastructure, critical communications, and adjacent markets. Formerly known as Filtronic Comtek plc, it changed its name to Filtronic plc in March 1998, was founded in 1977, and is headquartered in Sedgefield, the United Kingdom.