Extensions, or tools used for work, are things that everyone uses by hand. And the tool’s function is to help make things easier to proceed, so it represents a helper, power or collaborator who helps. In an abstract sense, it also symbolizes mental power or ability. A sickle can be said to mean an increase in wealth or wealth by cutting grain with a grain or a tool for cutting grass. But if you cut grass or grain and they are scattered without piling up, you may not get paid for the effort.