Prolific marketing & technical services manufactures a levelling jack for use as an adjustable support block for clamps and as a stopper or levelling block in fixtures or machines, as well as for levelling surface plates or other heavy duty workpieces. Unique design of this levelling jack does not allow the levelling spindle to rotate while adjusting, hence makes it suitable for fine level adjustment. This levelling jack is also available in conical and v-sectional head for other applications such as inspection.