HiLetgo G1/2" Water Flow Hall Sensor Switch 1-30L/min 1.75MPa Flow Meter Flowmeter Counter Water Flow Sensor

I've been using this product and the 3/4" version for the past year on my irrigation system. Excellent product. Simple to use. A couple of things to remember. First, the supply voltage says 5-24V, but there are some practical reasons why using a higher voltage may be a problem. If you are interfacing this to some IOT device which runs at 5V or 3.3V you are going to have problems. The output signal will be at the same voltage as its supply. So, if you power the thing at 12V, you are going to get a 12V signal back. Not really nice for a 5V or 3.3V input pin. I had a 3.3V IOT device so I tried using a Zener diode, but the supply current from the flow meter was too small to make this work. You really need to supply this flow meter with the voltage your IOT is compatible with. Don't try any fancy level shifting.The good news is I've been running this thing at 3.3V (it's only spec'd to 4.5V) and it works just fine.

Having a very hard time keeping this from leaking. Otherwise, it works as it should.

I never actually used it for what I bought it for, but I have tested it and worked just fine.

Results are +/- 40% accurate. High amount o f delta in actual results. But good for experimenting.