Many household items are designed to be fixed on the wall in order to save more space. Most household items that are not too heavy can actually be fixed by using expansion screws. What are expansion screws? In fact, it is a kind of nail, but it has a much stronger load-bearing capacity than ordinary nails. Its structure is also very simple, consisting of two parts: screws and expansion tubes. The working principle is to drive them into the wall together. When the nuts are locked inwards, the screws will pull outwards, thereby expanding the expansion tube and sticking it into the wall, playing a solid fixing role.