Hangzhou Strong Electric Co., Ltd. (SEC for short) is a professional company manufacturing and exporting porcelain insulators, composite insulators and line fittings for transmissions, power stations and substations and railway electrification. SEC has four subsidiary factories which are specialized in technical development. SEC establishes one set of quality management system. All the four factories have got ISO9001 certificates. The processes of quotation, handing order, quality management and technical support are strictly carried out according to the ISO9001 standard. All the factories have advanced manufacturing and inspection equipment. We control strictly in terms of raw material, manufacture, inspection, packing and others. SEC has good technology, competitive price and stable quality to support our customers and our products can meet IEC, BS, ANSI, AS and DIN standards. We are