Three poles means it switches all three phases simultaneously — required for any three-phase load from a small compressor to a lighting panel.
The XT2H 160 TMA designation indicates the frame size (160 A max) and the TMA trip unit — a thermal-magnetic adjustable type that provides overload and short-circuit protection. In a panel, this breaker occupies a standard 3-pole molded-case footprint and mounts via the rear panel or DIN rail adapter, depending on the installation kit selected.