Bests & Worsts Reviews from Amazon

In summary, this device is only marginally safe and has very simple, likely failure modes which make it possibly fatal to humans and other animals. I am an electrical engineer who bought this unit to test it for safety after having a discussion with a friend who used it to make a squirrel-resistant bird feeder. More detail: The instruction booklet did not seem to match the product at all - it describes standard pulsed electric fence energizers only. It claims that the unit meets UL requirements but there are no UL or other safety markings anywhere on the product or the packaging that I could find. The unit contains only a simple step-up transformer which uses two steel shunts to introduce excess magnetic leakage flux which limits the amount of current the secondary can provide. As received, I measured the open-circuit voltage as 980Vrms and the short circuit current as 8mArms. This would likely deliver about a 4 or 5mA shock which would likely be safe for a human but possibly not safe for a small mammal like a squirrel or rabbit. Much worse, though, is that it was relatively easy to remove the shunts from the transformer and after doing that, the open circuit voltage climbed to 1040Vrms and the short circuit current to a whopping 53mArms. This is well over the safe level even for a human. It could definitely cause muscle paralysis/inability to get away from the fence and even could cause burns and ventricular fibrillation. In my opinion, it is possible for the shunts to either be installed incorrectly or to be jostled out in shipment which could possibly allow the unit to fail in this way. With no provision to detect this situation and shut the unit down, I don't think this unit is safe enough given the risk of human and pet contact with the output. Normal pulsed electric fence energizers are much safer because they apply current only in very short pulses. This allows them to have an average current so low that it is not possible to cause severe physiological problems but a peak current high enough to hurt. The effect is similar to a series of static electricity shocks rather than a continuous 60Hz AC like this unit. I have no connection with any electric fence equipment manufacturer.