These slotting cutters were a waste of money. My analysis of this product showed that there were numerous defects, making it difficult to achieve precision cuts. The set was also inconsistent in size and could not be adjusted to fit properly. On the plus side, the cutters were made of durable materials and had a decent cutting speed. However, the defects far outweighed this positive aspect. I would not recommend this product to anyone seeking reliable industrial and scientific cutting tools.