Celduc was established in France in 1960. Celduc is a combination of two companies Celduc Transfo and Celduc Relais, and they deliver their productions of high quality Solid State Relays (SSR) and sensors to all over the world by means of more than 60 distributors.

CSR Ningbo CSR Times Transducer Technique Co., Ltd. was established in 1990. CSR used to deliver their products with the brand name of TEG. They deliver various types of sensors to be applied in many applications to Hong Kong, Europe, North America, Middle East, South East Asia and many different countries and regions.