1.certificated under ISO9001&QS16949quality system 2.High efficiency and low resistance filtration media 3.high quality Watsun is a leading manufacturer of filters in China. It was founded in 1990, and now Watsun has factories in ShenZhen,WuXi, Guangxi and branch company in HongKong,Singapore,Australia and all over China.Our filters are mainly used for trucks (VOLVO, SCANIA, IVECO, RENUALT, ...