The vibration is very strong and Definitely worth the buy!

The vibrate, my dog just lays down and won't walk. Lol it's easy to use, easy to charge. Id buy out again.

Absolutely works, the dog learned within a day or two to keep confined to the yard. Now, we don't have to worry about our son's dog running off while he is home from college. BUT most important don't have to worry about, Rhizzo, getting hit by a car on our pretty busy street! Wished our neighbor bought one before their dog was killed by a car. I suggested it a couple weeks before the accident.

I looked forever for the battery. Come to find out the battery is already in the collar but it doesn't look like a normal battery or a watch battery. It's completely proprietary thingy

Works very well. Day project with kids for a new dog. Need patience and the dog will stay within its boundaries. Kept raising the knob until he stopped testing his tolerance.

I am thankful and highly recommend this.