The parts make first a relatively "cheap" impression, because the upper part is placed via Bayonet on the ground spike. That makes no siginificant and wobbles pretty. Otherwise, just turn not much technology. Above a solar cell, which stores energy and then generates tones. In spike seems the battery to find the caches the solar energy.
Did you bury the spike once the shaking makes but no longer a problem. I recommend here absolutely NOT the tables to drill into the earth, but to really dig a hole and then einzubuddeln the part. Are turned on, the parts on the upper part. There is a button with which they can be easily switched on and off.
Use: hum tirelessly. At intervals of about 30 seconds a 1-second tone, which you can clearly hear sounds. We turn the parts now simply if we stay in the garden. In 15 - 20 meters away is almost nothing more to hear (that can also live with the neighbors). The voles we had seem to have been looking into the distance .. After 4 weeks of operation we can not "Wühlleben" find more. They are also not come back. The birds seem the parts by the way not to be interested.
Conclusion: a recommendation. Though it beeps constantly when the parts are turned on, but that can be switched off yes. Otherwise, very easy to assemble and effectively.
