An electronics assembly is described which allows three-dimensional movement of a printed wiring board (PWB) relative to an attached electronics subassembly. The subassembly is attached to the PWB by a coupling device which is capable of resilient deflection responsive to mechanical agitation while maintaining effective electrical and thermal communication between the subassembly and the PWB. The coupling device includes contact surfaces which enhance the reliability of the overall electronics assembly by minimizing the potential for detachment of the subassembly from the PWB.