12 or 24 Volt direct current motors also called VDC. The motor is the first essential element located inside the hydraulic power unit, which transmits the movement to the pump, creating the conditions to put the oil under pressure, which will make the entire hydraulic circuit and therefore the tail lift work. There are various powers expressed in Kw, normally the smallest are 0.5 kw, the most powerful ones in the tail lifts reach 3 kw. The engine is generally connected either directly to the gear pump, or to an aluminum manifold that acts as a central logic for managing oil flows. In this second case, the pump is positioned on the opposite side of the block and a drive joint is placed between the two.