Card- Mica covered with paper. White with black markings, graduated to 1/2 points with a decorated East point, edge of card graduated quadrantally in degrees. On underside are two metal balancing weights.
Needle- Flar bar type 6.9" (17.6cm) length with pointed ends and with a central aperture 2" (5cm) diameter to accommodate pivot gimbal. Attached to centre of needle is a ring or cylinder of brass, 0.5" x 2.5" diameter, to impart stability by lowering the centre of gravity.
Pivot- Inverted type mounted in double gimbal and attached to needle by two brass brackets.