Abstract: An electronic apparatus having a heat dissipative external enclosure is disclosed. The external enclosure having a containment wall from which depend extended surfaces or fins having a length extending vertically and defining channels therebetween. The thickness of the enclosure between external surfaces of opposed containment walls varying between a relatively thin portion and a relatively thick portion to provide an interior space having a relatively narrow portion and a relatively wide portion to accommodate components or units of corresponding different extent. The fins having outer edges, spaced from the containment wall, and having plain first opposed surfaces adjacent their outer edges, the first surfaces including a first angle therebetween. The fins or parts of fins adjacent the relatively thin portion of the enclosure also having plain second opposed surfaces inwards of the first surfaces, the second surfaces including therebetween a second angle greater than the first angle.