Extension springs are mechanical devices designed to absorb and store energy. They are made of coiled metal and work by stretching when a force is applied. These springs are commonly used in various applications, such as garage doors, trampolines, and clotheslines, where they provide tension and support. When the force is removed, extension springs return to their original shape, releasing the stored energy. Their design allows them to handle significant loads while maintaining flexibility. Proper installation and maintenance are essential to ensure their effectiveness and longevity in any application.