This is the rail rotation module. Whatever goes on to it will rotate by default 90 degrees, and then move on in the given direction if there is another rail block to go to. The degree of rotation can be modified by connecting activation blocks Connect from the rail rotator up to 9 activation blocks. Each active block will add 45 degrees to its rotation. So it is possible to dynamically change the rotation by just activating and deactivating the activation blocks. Nine active blocks will result in a constant rotation.