An object is tracked with a plurality of cameras, at least one of which is sensitive to both visible and invisible light. There is an outdoor air intake plenum which furnishes the fresh air and the condenser air for the condenser coil, and a return air plenum. The rolling element retainer is provided with a linking portion at each of two opposite sides thereof. Other interconnect techniques include direct coupling such as rod, ball, dual balls, bar, cylinder, bump, slug, and carbon nanotube, as well as indirect coupling such as inductive coupling, capacitive coupling, and wireless communications. The element is also arranged to receive the non-volatile memory device and to move the non-volatile memory device and the interface with respect to the body.