The Apollo Standard is an Ultrasonic contents gauge that comprises a tank mounted transmitter unit and a plug-in receiver unit with integral antenna. The tank transmitter frequently checks the oil level in the tank and transmits this to a plug-in receiver unit which displays the level on the easy to read LCD screen. The transmitter unit is compatible with the standard 32mm port fitted to modern plastic oil storage tanks. Optional multi-adaptor ensures compatibility with most steel tanks as well. Premium quality LCD display ensures readability from a wide range of angles under varying light conditions.