Product Description: SXN Internal corner miller is a special tool used for cleaning the internal welding seam of 90 degree PVC window and door. SXY External corner miller is a special tool used for cleaning the external welding seam of 90 degree PVC window and door. Cooperated with the Portable Cleaning Machine, the two tools can complete the whole cleaning of the PVC window and door. And it also can be used alone. It is safe and high efficent.