This one I just bought in December and started using about a week ago. Before I turned it on the dogs had been barking for two hours next door. Since then, only a bark or two and then silence.

https://www.amazon.com/gp/product/B07L1BSHP6/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1

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It looks like the other one I bought about four years ago is no longer available. The one I bought had okay reviews, but the dogs had been barking at all hours for two weeks straight, so I figured I'd give it a shot and return it if it didn't work.