The 3AH5 vacuum circuit-breaker is a real all-round device in its field of application. With its compact dimensions, it fits in all customary switchgear types. The comprehensive variety of types with different normal currents and short-circuit currents as well as various pole-centre distances for voltage levels from 12 kV to 36 kV enables its universal application for all medium-voltage requirements. The 3AH5 vacuum circuit-breaker consists of the pole assemblies and the operating mechanism box. The pole assemblies are fixed to the operating mechanism box via post insulators. The switching movement is transferred by means of operating rods and levers.