After fighting a losing battle with a packrat that kept getting into our shop, we broke down and ordered these. We have not had a problem since and are very impressed with the way they are holding up. I was afraid they would shake loose when we drove our vehicles, but they are staying in place and working as intended.

Saw 8 rats in my chicken yard yesterday. Deployed it in a plastic baggie in an outdoor shed and the next morning I saw none. Too soon to be sure, but they have been very bold at feeding time and this afternoon when I put the feed out I saw no rats at all. I will report back later if it works long term.

There was a huge pile of nutshells right where I placed the device on my engine (see pic). I vacuumed most away. I am pretty sure it was from mice infestation, not rats, though there definitely are rats running all around the yard and neighborhood at night. They are endemic here in this dreamland suburbia. Happy and fat, too.

I put the alarm in my Prius on January 26. I rarely drive this car, it's a back-up car. I drive it maybe once a week. I check the device every few weeks by opening the hood and switching to the TEST mode which gives off a sound and a few beeps to let me know it is still working. Also, it may be helpful to know that there were a lot of rainstorms this Winter and my car is kept in the driveway. No function issues
with the device relating to the wet weather.

And it has been 100% effective! Zero nuts or evidence of return of the mice. Before this device, I would use the peppermint spray that I bought on Amazon every couple of weeks. What a pain. It did nothing to stop them, btw.

Today I was walking by my car (April 28) and I heard this unusual beep. I realized it was the device signaling that the battery needed to be replaced.

So the three AAA batteries lasted exactly 3 months in this car that I rarely drive. So happy with all of that!

I waited to write about the device until I knew how long the battery would last so that this review would have some value to you folks out there. Good luck.

UPDATE July 22nd, 3 months later: Again walking by the Prius I heard the beep indicating a low battery. Easy swap out of the 3 AA batteries. (My original message said AAA batteries which was incorrect and I corrected it now.)

So it looks like this little device needs a battery swap out every 3 months. Again, I use this car infrequently, so I don't know how that affects the battery life. I am happy to report still no return of mice! Yay! New updated pic added today.

ours (ZN-509) is utilized beneath the belly of a trike which lives outside under a bike cover & a metal carport when not in use. our bike mechanic discovered a 'nest' (of some sort) fashioned in the compartment which houses the air filter of our trike last winter during annual "winterizing" & regular maintenance. at a loss, we decided to give this gizmo a try since our options are relatively limited. thanks to fellow, kind, community members' reviews, we bought this Loraffe model for the trike situation & another 'big brother' Loraffe for our 10'x12' metal shed out back (the much larger, triangular shaped, "4-in-1" model w/ two speakers & flashing LED's). both products have been used for a month & so far, so good! the one in the shed is plugged in 24/7 & the one on the concrete carport pad beneath the trike (this model above) runs on batteries. we haven't had to replace the batteries yet after 1 month but it's only "on"/ running during the evening & wee hours of morning. i see no indication of any rodent invasion in or around the trike since appropriating this unit about a month ago... again, so far, so good. i like the compact size of this model & might imagine it could impart lots of beneficial uses in a wide variety of places or applicable situations. iow's, it's small & portable & will run w/ standard AA's (3). yes, it's made in China. yes, it comes w/ a 1 year warranty. yes, you must remove the back plate to install batteries b/c that plate is secured by 1 tiny screw (the kit comes w/ a handy, tiny screwdriver + 8 tiny "zip" ties & 2 extra tiny screws). personally, i see no problem w/ this design but ymmv.

Conclusion: would I recommend the product (or, Loraffe in general)? so far, absolutely. would I buy again? whelp, hopefully not b/c we hope the two we've already invested in will work as intended/ advertised for years to come. the ZN-509 emits both ultrasonic sounds & LED strobe effect lights which 'cycle' through 5 stages about every 113 seconds. there is both a red indicator light & a beeping sound emitted from the unit (per manual) when low power (

Seems like an easy way to prevent a real problem of rodents chewing on the vehicle's wiring.