A cooling device for cooling electronic components mounted on a circuit board. The device comprises a hollow body defining a coolant transport circuit for circulating coolant fluid there thorough. The hollow body comprises a plurality of flattened regions linked by duct regions, wherein the flattened regions and duct regions are formed as continuous regions of the body. When the body is secured to the circuit board, each flattened region is configured to align with one or more electronic components for transferring heat away.