A hexagon nipple is a connecting element for pipe construction, which is fitted with a bilateral outer thread. As a result, the hexagon nipple can connect either pipes or fittings with an female thread. It comprises a simple straight connection, the thread and, in the middle, a hexagon. The hexagon can be screwed with a wrench. This type of connection is frequently used in heating construction, in tank systems, in water pipes or when building test benches in research and development, especially at universities. As a result of the bilateral external thread, the installation between two pipes, as a so-called adapter, is particularly easy because an installation position does not have to be considered.