Who knows if they work?
598593
I purchased two of these & they both failed in the first rain.  I returned them & installed the replacements in an area where they can't get wet.  When I got mine there was no switch but there was a convoluted method of starting & restarting the car to turn them on.  How dumb was that. Connecting them to the Hi-Beams dosen't seem much better to me. I ran a wire to an inside switch because I sure wouldn't want them running in a town or even at a traffic light.  My personal opinion is that they don't work anyhow.  I believe that deer whistles of both types have been professionally tested & the results indicated that they don't work.  I have driven past deer standing on the side of the road and they don't appear to pay a bit of attention to them.  And, my wife hit a deer last year with them blasting.
4552154
These were bought for soldiers that have been deployed... I have not received word if they're working or not. No news is good news...
2813824
Just got them and they work fine.  Test is whether they hold charge after they have been used a while.
303250
I haven't had a chance to do a severe test of them yet.  If they work as claimed, they'll be awesome.
2675252
What else can you say they work and look good.
3800895
yes these do work!! they may seem cheap at first, but after you figure out how to set everything up. They are awesome!!
3262142
Worked as expected....have not had the misfortune to see if they really work!
4564047
Getting to try them...looks like they will work.
2962478
They work.  Wire them up properly and they connect a device to a power supply.
1450178
Was a little hesitant they might not work, however, I'm pleasantly surprised that all is well. Arrived on time, as advertized.
4390707
People are looking for reviews to help them to know if this product actually work.  Does the book help? Have you used the product, how long did it take? What products did you use? The information and history should be inside the book, People want to know if you used the products and it worked for you.  That's it.
1625624
It was a gift , I don't know if they worked , but the price was good
4971868
Haven't used all of them, of course, but assume they will work when needed.
3446470
I bought them for a couple classrooms and haven't heard how they are working. Although I would have heard something if they weren't.
3633345
is that you are never sure they will work. This one did not. We are waiting to hear if we will be able to get our money back.
4153385
Some worked some didn't. The ones that work look great! Would give 5 stars if the company wasn't so hard to get ahold of to try and get the ones that don't work replaced. Only been a day I'll update on whether others are working or not in a month or 2.

Update: changing to 5 stars. The bulbs still work and the company contacted me regarding the bulbs that didn't work. Also someone broke into my truck and they still replaced the bulbs even tho I could not send the broken bulbs back!
2388604
I use them for clients. They seem to work well.