Drills need to be trued. Four of the eight bits in this set ended up off-center and wobbled too much. A centered drill is crucial for precise work. I use a machined Know Bit in my drill presses and milling machines to measure accuracy and runout. The drill chuck is up, but these bits are not. They came packaged in a hard plastic case and were clean and sharp so I was hoping for satisfactory results. not to be Keep searching.