Thanks for an interesting question.
I have always doubted the effectiveness of these devices and thought
it would prove to be interesting research. I searched for -
ultrasonic bat repeller - and discovered the following sites and
"Ultrasonic 500 Pest Repeller
The new revolutionary Ultrasonic 500 Pest Repeller has produced an
innovative breakthrough in pest and rodent control. The ultrasonic
sounds produced by this unit usually affect animals such as mice,
rats, and bats. Simply plug the unit in. Recommend placing another
unit on the opposite side of the room to increase coverage and
eliminate "Sound Shadows".
Designed to repel mice, rats, and bats.
Each unit covers a 500 square foot area.
ETL and CE approved
Plug unit in to an unobstructed wall outlet. Coverage in room can be
improved by bouncing sound off of reflecting objects, such as walls,
cupboard doors, and appliances, etc. This ricochet pattern will
increase effective coverage. Will not affect pets and appliances. The
ultrasonic waves may affect rodent pets such as hamsters, gerbils and
rabbits. Position the unit in areas away from rodent pet and it may
not cause discomfort for the pet..."
BR4004 Ultrasonic 500, 3 pack (1.3#) $17.95
I found an interesting paragraph at the Victor Poison Free page for
"Can ultrasonic sound waves be effective in repelling bats from attics
and other inside areas?
Sonic Technology Products makes no specific claims regarding the
effectiveness of the PestChaser in repelling bats because the way bats
respond to high frequency sound can vary significantly depending upon
the time of year. Between December and June, bats are roosting and
hibernating. They will not leave their nest, even if you introduce
high frequency sound. They give birth to their young in mid-February
and will absolutely not abandon them, no matter how noxious the sound
is to them. The only time high frequency sound produces a repellent
effect is from July through the end of October, after their young have
flown off and before they roost again for the winter. In our view,
bats are extremely beneficial and their habitat should be protected.
Bats are the single best controller of the insect kingdom. Bats may
eat as many as 600 mosquito-size insects in an hour. An average size
bat colony may eat 1/2 million insects in one evening."
Their device is $19.99 and can be ordered on this page:
Electronic Pest Control at
http://www.electronicpestrepeller.com/overa.htm has two devices on
sale at $39.95 and a deluxe model for $49.95. Although they do not
mention bats specifically, they seem similar to other devices that do
claim to repel bats. You might email them if you like their design.
At Safe Home Products we find a higher end model:
Transonic IX-L: Repels All Pests
Banish Pests with Sounds They Can't Stand
Versatile Ultrasonic and Sonic repeller for:
Small animals (raccoons, skunk, squirrels) and Deer
Rats & Mice
Spiders, fleas, ticks & other flying or crawling insects
"Psychoacoustic Jamming" Electronic Solution: Intense, variable pitch
ultrasonic and sonic sound waves repel pests. This noisy, hostile,
dynamic sound environment is intolerable to pests, yet friendly to
pets, humans and the environment.
Continuous, Maintenance Free: Up to 2000 square feet of easy pest
control. Use the 110vAC adapter, a 12 volt battery, or optional
cigarette plug attachment.
Customizable Controls for your Infestation: Different settings repel
different pests. User-friendly controls on the back let you choose
frequency, mode and speaker direction. On some settings, humans can
barely hear the sounds.
This device sells for $94.50
As I am suspicious of the effectiveness of these devices, I checked a
few pages on bat control to see how they thought ultrasonic bat
INTELLIGENT CONTROLS FOR BATS
"Ultrasonic devices do not repel bats for long, so why use them? Try
loud, heavy metal music. "
Hmmm, interesting thought.
I was also truly surprised that there were not more of these devices
for sale on the Internet. I checked several other search engines and
found the same hits as these plus one device for $475, but I thought
that too pricey to mention. So, I am afraid this is the selection the
Internet presents for ultrasonic bat repellers.
I trust this will lead you to the device you saw previously or an
Good luck repelling the unwanted critters.