... Quality system 2.High quality raw material and reach OEM quality . Watsun is a leading manufacturer of filters in China. It was ... , France, Australia, Poland, Russia,Japan, Singapore, Iran, Iraq, Sudan, U.A.E, Russia, South Korea etc. Our customers come from more ... ) Thread size:Up: 1″-14 Down:M96×2.53) Advantages:a) High quality raw materialb) Low resistancec) Long service lifetimed) Durable ...