The H45MEY demolition hammer features the HiKOKI AC brushless motor with no wearing parts such as carbon brushes, commutator or a field coil. This combined with HiKOKI's original compact controller guarantees powerful performance and extends the overall lifetime of the tool. Equipped with HiKOKI's original, compact high efficiency inverter circuit, the demolition hammer works with an engine generator that doesn't have an on-board inverter. The brushless motor runs cooler, and its performance isn't affected as much by voltage drop from long extension cords onsite. This vastly improves electrical efficiency. The internal double-insulation construction with a very sturdy aluminium die-cast body and a plastic internal stator holder makes the housing more rigid, significantly enhancing durability of the motor unit. The built-in electronic control circuit adjusts the impact rate according to applications, and the four-step impact rates can be selected by the impact rate selector switch.