Nice
but they probably don't work, most independent and reputable studies haven't shown any great difference in pest deterrence.
My own test - I tried one similar - showed no difference.
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social hand grenade I was a lurker before you were a lurker, Thu 15 Mar 2012, 22:06,
Reply)
Had a quick Wiki
Turns out Cockroaches detect electromagnetic waves through their genitals so rather than repel them it probably just gets them off (well in my mind anyway)
en.wikipedia.org/wiki/Electronic_pest_control
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chuff monkey I AM him, Thu 15 Mar 2012, 22:16,
Reply)