Contain an unlimited number of pets with our smallest wireless receiver collar that features a rechargeable battery and 5 adjustable levels of static correction. This extra receiver collar can be used to add another dog or as a replacement collar to the Stay + Play Wireless Fence (PIF00-12917). This collar is also compatible with the original Wireless Containment System (PIF-300). Formerly PIF00-12918, this new version of the collar now comes with the charger. Intended for dogs over 5 pounds with a neck size between 6" and 23". Fully Waterproof and rechargeable.