For example when installing a cupboard you can take great care that everything is aligned correctly and then the hinges are fitted. Try to keep the screws centered in the screw holes, this is a problem to say the least. Even the best shot will not replace any of them. The problem is that when the hole starts and it is moved, even if only slightly, the screw sticks out at an angle, making the whole project look like it was made by a third grader. a set of them that came bundled with four. There are nine in this set. They can guarantee you are the right size. The uniqueness of this set compared to my other sets is that you can take it apart and if needed replace the drill with the one you supplied or run through a drill sharpener. This is no frills packaging. The inner bag is hermetically sealed and can be cut open with scissors. In terms of storage, the outer plastic packaging, which is white on the back and transparent on the front, has a fairly extensive zip function, making it great for storage and making it easy to see the contents of the pack. All in all a good set at a good price.