INR insulation bearings has been patented in China and got patented letter. Now it is widely used for the application of electrical motor and generator equipments.It has norminal 100um~150um layer of ceramic to protect the bearings against electrical current passage and to extend the life of the bearings and asssure the stable running of the equipment. Our design of cage can be: J (Steel rivet cage),M(Two Piece brass cage),or PA6.6.