DC0-110V Liquid Water Level Sensor, Float Sensor Switch, Male Thread 1/2 NPT 304 Stainless Steel, Suitable for Liquids of Different densities, pressures and temperatures: Amazon.com: Industrial & Scientific
The Basics of Float Level Sensors: How They Work and Why You Need Them - ICON Process Controls
Water Level Switch, Liquid Level Sensor, 3.94in Liquid Float Switch Stainless Steel Float Level Sensor for Water Tank: Amazon.com: Industrial & Scientific
Stainless Steel Float Switch Tank Liquid Water Level Sensor Double Ball Float Switch Tank Pool Flow Sensors 10W Control Pump
Amazon.com: Float Switch Water Level Sensor, Stainless Steel Double Ball Fish Tank Liquid Float Switch Water Level Controller for Water Tank, Pool, Sink, Fish Tank, etc(4 Size)(100mm) : Industrial & Scientific
Liquid Level Sensors - Floats - CTG Technical Blog