This field allows you to change spindle rotation from clockwise (CW) to counter-clockwise (CCW) by placing the correct text in this box. The only valid entries are CW or CCW. Few machines support the CCW option. Check your machine's specifications to see if it can output the code necessary to start the spindle in either CW or CCW. If your machine tool does not accept the CCW command, then you will likely get an error when the NC code file is run.