First, the case is poorly designed. Every time you close it, the pieces inside fall out of their slots, leaving you with a complete mess when you open it again. The quality of the components is extremely poor. You cannot see the size markings stamped on the bits. Good luck finding who you are looking for. And finally, the 1/4" bit broke when I tried to hand tap the threads without much effort, suggesting the entire set was scrap steel. Don't waste money.