Thought I’d share since a put a lot of thought into this issue before making a purchase.
I’ve been living in a house with a backyard pool for a little over a year. My biggest pool concern is letting my dog out back go to the bathroom and him falling into the pool one day, especially once he begins getting progressively older, weaker, blinder.
I purchased the photographed device, despite some mixed reviews. I think it’s primarily intended for kids, but pets are also mentioned in the description. The transmitter is shaped mostly like an air-tag and can be wedged into a rubber air-tag holder sold at pet stores.
After a month of ownership, i definitely recommend it. If it’s exposed to a drop of water, the receiver will immediately blast a loud, shrill alarm inside the house that is impossible to ignore. The main criticism of reviews is that it gives false alarms. I’ve had a total of one false alarm so far. I think the dog drooled onto his collar, setting it off. I can definitely live with the occasional false alarm in return for increased peace of mind when I let the dog outside for a minute.
I realize this alarm is not as fool-proof as constant supervision, but the dog has to go outside X number of times per day and I’m not going to let perfect be the enemy of good.