This is a Gallagher electric fence tester, but it's no longer working. More info in comments. : r/AskElectronics

Electric fence voltmeter led (i think) not working anymore, if

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INSTANT REASSURANCE YOUR ELECTRIC FENCE IS WORKING - Place the Gallagher Electric Fence Indicator permanently on your fence line and simply look for

Gallagher Live Fence Indicator | Detects Electric Fence Energizer Pulse | Visible LED Light Indicator Alert Device That Clips to Wire or Tape Fences

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