HOBI Ultrasonic Animal Alert Whistle

[shogun]

HOBI" ULTRASONIC ANIMAL ALERT WHISTLE
A N I M A L S . . . I N S E C T S . . . B I R D S
NO BATTERIES - NO WIRES - INEXPENSIVE
EASILY MOUNTED . . . . . EFFECTIVE ON ALL MOVING VEHICLES ABOVE 30kph . . . . . 400m RANGE

Sounds to good to be true.
Any experience with such whistle?
Hitting a deer is quite costly and dangerous, so 25 $ might be a good investment
http://www.austhobi.com/index.html

[attack eagle]

Those were proven to be useless.

Deer can hear your CAR, by itself, far more than 400m away...


I couldn;t find the picture I saw some years back of a deer-car collision... ironically the car had those damned deer whistles on it.

nice article, which pretty much sums it up...
http://www.ibmwr.org/prodreview/deerwsle.html