inexpensive

Float switch, plastic: VK1114
Simple, cost-effective plastic float switch made of PP with a hollow float made of PP. This float has excellent buoyancy, making this float switch suitable for use in liquids with densities from 0.65 g/cm³.
This level switch is mounted from the inside and fixed in place with the enclosed nut. The existing seal ensures a tight installation. It can be used almost anywhere thanks to the wide temperature range of -10 ... 110°C.
You can easily change the switching function from normally open to normally closed by turning the float through 180°.