http://www.treklens.com/gallery/photo423700.htm (http://www.treklens.com/gallery/photo423700.htm)
http://nl.worldmapz.com/photo/137223_ZH.htm (http://nl.worldmapz.com/photo/137223_ZH.htm)
http://nl.worldmapz.com/photo/137186_ZH.htm (http://nl.worldmapz.com/photo/137186_ZH.htm)
the Netherlands lighthouse,
Jagged device is confrontation with birds
hope that birds do not stopping here,
so that keeping clean,
do you think so ?
Definitely! I also seen some other ways - special pins in the top of LED lamps.