Pet Tracer collars are remarkable. The dual technology in them really sets that apart. GPS alone wasn’t enough to find our missing collar but when combined with the radio signal it meant finding it easily! Not long after getting these collars for our two young cats one cat managed to come home without a collar (my fault for not making it tight enough). GPS data was focused on our garden but moved around a bit and despite searching we just couldn’t find it. The help desk at pet Tracer were brilliant. They explained that a moving GPS signal could mean the collar was under something. As instructed we set up a mobile home station to use the radio signal for a closer search. We couldn’t understand why the signal was highest on our decking until we realised that the cats could get underneath and lo and behold, a collar was visible through the gaps. One collar retrieved and put back on! Amazing! So impressed that it worked even when the collar was hidden underneath the decking. Really reassured that if we ever lose a cat the collar will enable us to find it again. It has already proven to us how effective the GPS/radio technology combined is. So happy with our purchase! Thanks PetTracer!