Spacer sleeves are used in various industries to maintain a constant distance between assembled components. They are an important element in electronic designs where insufficient distance between system parts may adversely affect the operation of the whole (for example by creating unwanted electrical connections). Spacer sleeves can be made of metal or plastic, and can be equipped (on one or both sides) with different types of threads for easier assembly. In addition to cylindrical bushings, hexagonal bushings (hexagonal in cross-section) are also popular. A well-chosen spacer can determine the quality of a project and its durability.