A portable electronic device can include a housing defining an aperture and a display positioned in the aperture. The portable electronic device can include a number of components that can provide desired functionalities and levels of performance. For example, the device can include one or more couplers that interconnect various portions of the housing together. Additionally or alternatively, the portable electronic device can include one or more millimeter-wave antennas. Additionally, or alternatively, the electronic device can include one or more grounding elements or layers that reliably and electrically ground the display to the housing.