I have one on my new labradoodle for a couple reasons and after seeing people test them out, I’m confident that it would do its job if he ran off. Think about what happens when you lose your dog. He runs off, likely staying in your neighborhood or being picked up by a neighbor or animal control. If either happens, the neighbors will usually travel around for a bit looking for a possible match to the owner. If animal control happens to pick them up, they are in contact with a lot of people, especially once they reach the facility. At some point in either of these scenarios, the dog is highly likely to come in contact with multiple people using iPhones which should give you at least some idea of where he is or is going. Even if he is evasive to good samaritans, you will still likely receive pings as people try to catch him and get a general sense of his location. Add that with an attached phone number to the collar and you are highly likely to get your dog back.
Personally, I have a thicker leather collar on him so I was able to take a good tape and wrap it around part of the collar. You’d hardly recognize anything is there, let alone a tracking device.
Initially, I was using the iFixit hole method to attach and it actually worked well but I wanted it moving around a lot less long term.
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