Bowl-Black painted alloy, filler plug at bottom, expansion chamber at fore end. Corrector magnet carrier on top. Inside of bowl black with a luminous wire lubberline mounted across diameter of curved verge glass.
Card-Dia. 2.75" (7cm) Vertical metal ring painted black with white markings, graduated to 360 degs., attached by four metal struts to pivot at centre.
Pivot-Mainly unsighted, but stem can be seen attached to base of bowl.