The BK ball screw fixed end support are sometimes referred to as pillow block style. Mounting holes are provided to bolt these to the base where your ball screw will operate. The BK ball screw end support contains two angular contact bearings that provide both axial and rotational support for the ball screw. There are 3 precision classes C3,C5 and C7 bearing supports. It is suggested to use C3 support units with a C3 ball screw. And C5 ball screw can be used with C3 or C5 support units, which enables the support units precision to match the ball screws precision. C7 ball screws should only be used with C7 support units. Our standard ballscrews are supplied with machining that will work with these supports without modification.