Stepped water supply is a non conventional technology that irrigates water crossing over the bur for effective cooling. It is enabled by stepped supply of water and air structure for wider water diffusion. (Patent pending) Effect: Stepped Water Supply technology enables evenly supplied water. This can be very effective for eliminating the heat on the affected area generated by cutting, and also effective for eliminating the debris. It eases the heat-caused pain for patients, and therefore creates more relaxed setting of treatment improving the quality of treatment as well.