Magnet coatings is a non-contact coupling, which is generally composed of two magnets inside and outside, separated by the isolation cover in the middle, the inner magnet is connected with the driven part, and the outer magnet is connected with the power part. Magnet coatings not only have the functions of elastic coupling buffer vibration absorbing, its biggest characteristic is that it broke the traditional coupling structure, using new magnetic coupling principle, implementation not by direct contact between driving shaft and driven shaft can force and torque transmission, and the dynamic seal into static seal, zero leakage. So it is widely used in the leakage of special requirements of the occasion.