The device is relatively cheap. - Maybe that's one reason that it does not work as expected. Batteries must be constantly renewed and will not always work, the vibration times, thus working again for a while it is necessary to take the batteries out and hang around or knocking on it ..... It does not work reliably, unfortunately, because in and of itself would be the certainly something great. Our dog would really appeal to the fact - even if it sets only very modest he listens better to commands and is much more attentive. But as mentioned, the reliability can be desired. Perhaps we should invest more (no upper limits are set as yes, we also have a device to EUR 350, - seen ..).
