Very unreliable. Lose signal all of the time + weak sound emitted.
They are that bad that it should be reported as a scam. Ihave 6 tiles and have used them for 3 years. Stay away from them ! The sound they emit is very weak. Also they lose their connection continually, even in close proximity. It will generally find something if it is within two metres. Sometimes the tile has a new battery and does not find the tracker even when it is within 2 metres. Conclusion: absolute rubbish. Nothing but a scam ...