NOVELTY - Apparatus for mechanically and electrically connecting two electronic devices comprises base unit (100), which is mechanically connected with a structure including a first electronic device; and replaceable unit, where a diameter of threaded, electrically conductive inner surface of round outer ring (110) of the base unit corresponds to a diameter of an outer surface of an outer ring of the replaceable unit, and all threads (104) are of the same pitch such that the replaceable unit may be screwed into the base unit, forming one assembled unit.    USE - Apparatus for mechanically and electrically connecting two electronic devices, one of which may be a solar panel.    ADVANTAGE - When screwed together, two sets of threads resist pulling the two apart, providing superior holding power, as well as allowing for additional torque compared to a conventional nut and bolt.    DETAILED DESCRIPTION - Apparatus for mechanically and electrically connecting two electronic devices comprises:    (A) base unit (100), which is mechanically connected with a structure including a first electronic device, where base unit comprises a round outer ring (110) including a threaded, electrically conductive inner surface; a connecting piece spanning the outer ring; an opening (116) in the connecting piece for through-passage by a first electrical lead, which is electrically connected between the first electronic device at one end and the threaded, electrically conductive inner surface at the other end; and a center post comprising a threaded, electrically conductive outer surface, where center post is oriented along an axis of the outer ring and perpendicular to the connecting piece, where second electrical lead through the opening in the connecting piece is electrically connected between the first electronic device at one end and the threaded, electrically conductive outer surface at the other end; and    (B) replaceable unit comprising an outer ring including a threaded, electrically conductive outer surface; a connecting piece spanning the outer ring, forming a cavity bounded by the outer ring and the connecting piece, where connecting piece has an opening at the center of the connecting piece corresponding to the position of the center post, where opening includes an electrically conductive inner surface; and a second electronic device within the cavity, where electronic device has a first electrical lead electrically connected to the electrically conductive outer surface of the outer ring and a second electrical lead electrically connected to the electrically conductive inner surface of the opening, and where a diameter of the inner surface of the outer ring of the base unit corresponds to a diameter of the outer surface of the outer ring of the replaceable unit and further where diameter of the outer surface of the center post of the base unit corresponds to the diameter of the opening at the center of the connecting piece of the replaceable unit, and all threads (104) are of the same pitch such that the replaceable unit may be screwed into the base unit, forming one assembled unit.    DESCRIPTION OF DRAWING(S) - The drawing shows a top view and a cross-sectional view of a base unit.    Base unit (100)    Threads (104)    Round outer ring (110)    Center piece (112)    Opening (116)