These are great parts for work projects. I make small items on my lathe and every once in a while I have to drill out the center to insert a brass tube (used to make handles) and these and just sharp end pieces do the job well. When a drill needs to be drilled a few inches, the tip helps keep the drill centered. I also like that they have a 1/16 pitch, which is important for pen making and some other hobbies. This means all my bits are in one set and I don't have to search for odd sizes and then pay $12 for 1 bit. The price of this set makes it a great purchase. But I also wonder why on earth anyone would make 27/64 inch stuff as with all bits that can be prone to sticking, but I've found that this is especially true with wood like burl or wood from denser rocks the case is. Woods like Katalox, Padauk etc. be careful and it's not a problem. even a few custom sizes you might need and it comes with a screen printed embossed metal case with bit sizes making it easy to organize but quick to find what you need.