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Shenzhen Sino Testing Services Co., Ltd.（STS）, a national high-tech enterprise, Member unit of Explosion proof Electrical Appliance Branch of China Electrical Equipment Industry Association，Shenzhen specialized, refined, unique and innovative small and medium-sized enterprises,has long been based in southern China. It is a testing and certification organization specializing in explosion-proof certification and coal safety certification. Its business covers domestic and international explosion-proof testing and certification, coal safety and mining safety certification, explosion-proof construction and renovation, explosion-proof qualification certificate agency, explosion-proof system training, etc. It can provide customers with one-stop services from explosion-proof design, testing, certification, on-site inspection, engineering construction renovation, training, etc.