Bowl-Ironium (?) plated, filler plug on foreside, expansion chamber at top. Inside of bowl black with a white painted wire lubber line mounted across diameter of curved verge glass. Mounted in a bracket on coil springs with felt pads. Corrector magnets are fitted to underside of bowl, consisting of four discs each carrying a pair of magnets.
Card-Dia. 2.75" (7cm) Black plastic (?) vertical ring, with white markings, graduated to 360 degs., attached by four black wire struts to pivot at centre.
Needle-Two needles of circular section suspended on wires below card.
Pivot-Inverted type, pivot stem carrying jewelled pivot cup mounted to base of bowl.