Bowl-In grey painted aluminium casing. Black plastic filler plug at side. Expansion chamber unsighted as bowl is secured in its outer casing. Inside of bowl unpainted, fitted with four lubber lines mouted 90 degs. apart, these consist of black lines carried on white plastic strips secured to base of bowl. The high domed verge glass has the photo-electric mechanism secured to its inner surface.
Card-Dia. 6.26" (16cm) White plastic ring with black markings, graduated to 360 degs. Secured to black plastic float at centre.