Zhejiang Tenglong Electrical Apparatus Co., Ltd. which was founded in 1978 is located on Sanmen bay of East China Sea. It is one of the earliest Companies in designing and manufacturing tap-changers for transformers. With the abundant experience in design and manufacture of transformer components for years, and the Combinations of High-Scientific theory and Modern design theory in practice, as a result Tenglong has obtained lots of patents for those reasons we have mentioned above. And this is also one of the key reasons why Tenglong has excellent quality products and becomes the main supplier for transformer tap-changers in China. People oriented and honesty is the everlasting motto for all Tenglong People. And Tenglong people are famous for their hard struggle and creative minds, thus enable Zhejiang Tenglong Electrical Apparatus Co. Ltd. to walk on the right track to the sustainable development.