Gemini power hydraulics manufactures gemini automatic oil levellers, tom 500 and tom 1000. These are manufactured for automatic adjustment of the optimal oil lubrication level within a bearing housing, gearbox, crankcase or similar oil bath lubrication application. The automatic oil levellers allow effective adjustment of the correct oil level during running conditions, optimizing machine performance and increasing the service life of the equipment. Furthermore, they automatically compensate for oil leakage and offer possibility of visual inspection of the oil level. Oil is topped up only when required and hence providing constant and accurate oil level monitoring. Tom model of the automatic oil leveller, uses only gravity and atmospheric pressure and further adjustments are required once installed. The transparent body facilitates rapid inspection for contamination. Application of the automatic oil leveller : tom finds use in automatic adjustment of optimal lubrication oil level in crankcase, gearbox or similar splash/bath lubrication systems.