An electronics assembly 10 is provided, including a housing 12 and at least one electronic power device 18 positioned within. A heat sink device 34 is positioned within the housing 12 and is in thermal communication with the electronic power device 18. The heat sink device 34 includes a fluid vessel 44, a fluid input port 50, a fluid output port 52, and at least one fin insert 60 brazed into the fluid vessel 44. The heat sink device 34 is in fluid communication with an automotive radiator 46 such that coolant 48 flows from the automotive radiator 46 through the fluid vessel 44 thereby cooling the electronic power device 18.