Moeller Fuel Gauge, Mechanical, for 12" deep tansk. Mechanical Sending Unit Swingarm. Mechanical Sending Units with a direct sight gauge or with the optional *conversion capsule (MOE-35727-10) gathers fuel level information with the float. While accurate, the gauge will fluctuate as the fuel in the tank "slosh" around the tank when boating because of the moving parts - the float. Direct Site Gauge is complete on unit. * Conversion capsule converts fuel level reading from standard direct site gauge to electric dash mounted gauge (33-240 Ohm's)