first casing the second casing could include a hollow portion to encase or otherwise contain electronic circuitry mechanical equipment or other user interface processing or communication equipment the second mating surface could be any of the surfaces of the second casing intended for mating or joining with another casing mounting plate or module to form a stacked configuration with the second casing operation 503 includes coupling the first mating surface of the first casing to the second mating surface of the second casing through the raised contact nodes where the raised contact nodes contact the second mating surface to discharge electrostatic discharge energy between the first mating surface and the second mating surface the first casing is joined to the second casing in a stacked configuration in this example where the first casing joins to the second casing at the associated mating surfaces the first casing and the second casing could be joined to each other by fasteners such as screws or by an adhesive weld or other coupling devices or materials including combinations thereof the raised contact nodes of the first mating surface conductively contact the second mating surface and thus conductively couple the first mating surface to the second mating surface.