Works great on my little chihuahua's.

I purchased this collar for my barks-alot Shih Tzu. It stopped the barking on the first day. The collar is no longer working even after a change of batteries, but he doesn't seem to realize it. He only barks now when he is not wearing the collar.

The battery compartment, or on/off switch, is very difficult to open or close. It bent after a few times using it so it was no longer operable. Jeffers replaced it, and the new one is also very stiff, but so far functions ok. It does work to control my

I have three barkie Chihuahua's ranging in weight from 4 pounds up. I size these collars down to fit them and the barking has stopped. I also use these collars on my bigger dogs. THEY ARE EXCELLENT BARK DETERRENTS!!!!!!!

the collar has to be in the exact right position for it to work, when it does work it gives a good shock