Review on ⏰ Jayron Mechanical Maintenance Hour Meter: AC 110-250V Analog Clock for Generator, Compressor, Mowers, Snowblower - Waterproof Design, Easy Installation - Battery-Free, Long Life by George Bridgewater

I bought this to run in parallel with my drain pump. I need an hour meter that records pumping time and doesn't require a battery to work. This is a mechanical device, so memory is not lost due to battery wear. It works by generating a pulse once per second which then advances the counter. You can hear pulses once per second once it starts counting. It's like a battery powered wall clock. To test this device, I plugged it into a power cord and connected it through a wattmeter. The meter could not determine the current or power, but the meter started counting. After 12 hours, the counter agreed with the elapsed time. Initially I was worried that it would take a while for the meter to start if the power went out. But in testing I found that it starts within 1 second. It seems to be doing what I want, so I'll install it now.