This instrument is mounted on a pivot on a table designed to hamg in the gimbal ring. It is a circular box with a glass front. It contains a needle consisting of two springs about 1/4" apart at the centre and placed one abve the other. There is a needle lifter and a bar for moving the balance weight from outside. The two halves of the case are coloured red and blue and the spirit level is on the top (see ACO.94). Width of gimbal bracket 11.5" (13.2cm). A plaque in Japanese on reverse