I had ordered the small window alarms to my window to back up a little. When unpacking and try worked only 1 alarm right away in the other two worked nothing. As a return shipping is not worthwhile at the low price, I once opened and found that a capacitor had come loose from the soldered joints an alarm transmitter. I then angeschmissen my soldering iron and solder the capacitor again and what can i say it works. The same I did with the second alarm device and this now works.
So if one has money to give dan he can buy these parts calms or send me a small gift, it comes to the same thing you get no value for the money.
The volume is also incorrectly specified in the description, on the product packaging, the Dinger with 85 dB and 110 dB not be specified.
