This is a highly damped fuel level gauge which matches either our 5-hole adjustable fuel level sensor or the VDO 5-hole float type fuel level sensor. The gauge expects a resistance input of ~10 Ohms empty to 180 Ohms full.
The gauge is supplied a 'U'-shaped fixing bracket and thumb nuts along with a 12v /2w illumination bulb. Night illumination is classic white.
The gauge size of 52mm denotes the outer diameter of the main body of the instrument and hence a 53mm to 54mm diameter hole is required in the dashboard.
52mm Wiring diagram can be found here.