I had a previous tracker for my cat which I got because she went missing one night a couple of years ago. By the utmost good luck, we found her within 24 hours but if there'd been an inch of bad luck involved, we might never have seen her again. The first tracker was great for me but it had flashing lights which must have been stressing her out as within 3 months, she had groomed herself bald on her underside. So back to square one.Then I found PetTracer and learned that is has no flashing lights - only an LED which you can activate if you're looking for your pet in the dark. PetTracer is fantastic. She has adapted to it really well - as I say, there are no flashing lights and she appears to be very comfortable with it on. Best of all, the battery lasts the whole weekend (if we're away) and it can last for longer if you change the tracking mode - which we'll be doing when we go for longer holidays. Absolutely brilliant and what peace of mind. Worth every penny.