Series K disc springs are specially designed as preloading springs for use with radial ball bearings. They help maintain positioning accuracy of the bearing with no end play. They also minimize vibration and shaft deflection. Proper preloading will increase bearing rigidly and eliminate excessive running noise. Ball bearing disc spring are available in two different styles. Plain ball bearing disc spring(OD range from 9.80mm to 358mm); Slotted ball bearing disc spring(OD range from 9.80mm to 94.50mm) Pls contact with us if you need further information.