Easy-to-install, battery replaceable system is great for any size dog. You choose the configuration to not only keep your dog safely at home, but also clear of out-of-bound areas such as gardens and pools. Patented run-through prevention offers secure, reliable containment. For use in the US only. This unit is compatible with all US 110v outlets and are not to be used with 220v international voltage. SportDOG Brand® is the most recognized brand in the electronic dog training category. Our products are known not only for their quality, but also for being the best value for the dollar out there.