A side mounted waterproof float switch (HCSENS0015) which uses a magnet embedded in the float, and a magnetic reed sensor switch in the body to sense when the water level goes above a fixed point. The reed switch is mounted in a sealed non-conductive material. A silicone washer provides a water tight seal around the fixing hole.

Specification:

Contact rating: 10W
Max current contact current: 1A
Max switching current: 0.5A
Max Voltage: 100VDC
Contact resistance: 100mOhm
Temperature rating: -10 to +85oC