Abstract: A step installation structure of the truck includes at least a step support and a fixing member. Said step support is provided with a base for setting with the step assembly, a frame member is provided on the rear side of the base, which is used to insert inside the receiver hitch of the truck; said frame member is set with a plurality of perforations. Said fixing member is provided with a clamp body and a threaded bolt, the clamp body is set with a clip plate and a push plate which are arranged perpendicular to each other, the clip plate and the push plate are provided with a screw nut thereon separately; the end of the threaded bolt is provided with an anti-shedding member. Therefore, with the innovative fixing member, the step support can be more securely combined with the truck.

Abstract: A step installation structure of the truck includes at least a step support and a fixing member. Said step support is provided with a base for setting with the step assembly, a frame member is provided on the rear side of the base, which is used to insert inside the receiver hitch of the truck; said frame member is set with a plurality of perforations. Said fixing member is provided with a clamp body and a threaded bolt, the clamp body is set with a clip plate and a push plate which are arranged perpendicular to each other, the clip plate and the push plate are provided with a screw nut thereon separately; the end of the threaded bolt is provided with an anti-shedding member. Therefore, with the innovative fixing member, the step support can be more securely combined with the truck.

Abstract: A heat-dissipating circuit board assembly is composed of a heat-conducting base board and a circuit board. The heat-conducting base board includes an insulating heat-conducting layer disposed thereon and a plurality of bonding pads disposed on the insulating heat-conducting layer and never connected with one another. The circuit board that is single-layered or multiple-layered includes a plurality of electronic components at at least one side thereof and a plurality of heat-dissipating zones at a side thereof. The heat-dissipating zones are connected with heat-generating elements of the electronic components and in a corresponding position to the bonding pads. The heat-conducting base board is connected with the heat-conducting base board by the melted bonding pads that are melted by heating and further disposed therebetween.