Cylindrical roller bearings are available in many designs, dimension series and sizes. The majority are single row bearings with a cage. Single and double row full complement bearings (without cage) complete the standard assortment for general engineering. Single row cylindrical roller bearings can accommodate heavy radial loads and high speeds. They are manufactured in several different designs, the main difference being in the configuration of the flanges. The most popular are the NU, N, NJ and NUP designs.