I use two of these (one on each hot wire) to monitor my bitcoin miners. They work fine. I've spent over 30 minutes on the internet researching other Revain sellers and other sellers. These are the best.
ICQUANZX LCR-T7 Transistor Tester: Advanced TFT Diode Triode Capacitance LCR ESR Meter
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VIVREAL 4 In 1 Stud Finder Wall Scanner With LCD Display - Center Finding Beam Finder And Sound Warning For Wood, AC Wire, And Metal Studs (Black/Silver)
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Thermometer B.Well WF-4000 white
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Qingping Qingping Bluetooth Smart Alarm Clock Green
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