Capacitance fuel level sender 19" long, 3" bendable section is between black mark and mounting flange, 1/2" OD, 12 or 24 VDC (28V MAX) input, 0-5 VDC output.  Typically used on Helicycle tanks.
Typical SAE mounting flange          Instructions
The nominal supply range is 11-28vdc.  The current is less that 30 milliamps (.03 amps).