PetSafe In-Ground Radio Fence is safe and effective for all pets over 8 lbs. It's great for training pets to repect boundaries. PetSafe In-Ground Radio Fence works by delivering mild static correction through two Contact Points that touch your pet's neck. If your pet croesses the established barrier, a correction will be sent to get your pet's attention, but will not harm them. The adjustable collor allows you to create a perfect fit for your pet. Plus, there are two sets of contact points to choose from depending on the length of your pet's coat. System inludes Transmitter with power adapter UltraLight Receiver with Adjustable Collar Step-by-step installation and training video CD Operating and training guide Battery Included (RFA-67) 500 feet of wire and 50 training flags Only 4 steps to a contained pet! Will transmit up to 10 acres or 2,800 feet of wire Boundary Width is 20% Warning Zone and 80% Static Correction ZoneClick here to download operating and training guide in pdf format.