S13 is our company on the basis of the original S11 distribution transformer, through new materials. The research and application of materials and new technologies and the combination of independent innovation and technology introduction. Through the optimization and innovative design of the core and coil structure. Reach a reduction.No load loss and noise purposes. Self-developed products.No-load losses decreased by an average of 37%. Noise level and current national standard J8/T10088-2004 compared to the average decline of 20%, product performance level up to the domestic advanced level.