Dirty Electricity Meter by Trifield - Model EM100 - EMI Power Line Noise Analyzer - Know Your Electricity @ Home, Office, Shop - Made in USA by Alphalab, Inc.
TriField
Powertronics Probe 100+ - USB Power Line Monitor, Black
Powertronics
MATRIX Power Meter MPM-1010, Watt Meter 15Hz-650Hz, AC/DC Power Meter Current and Voltage Test, High Precision Multimeter with Upper and Lower Limit Set and Sound Light Alarm
MATRIX