The kit contains all you need to contain your dog in a yard up to 1/3 acre, including the stubborn dog collar. The transmitter can cover up to 10 acres. For dogs over 18 lbs that are stubborn or hard to train. Receiver has 5 levels of programmable correction including a beep warning tone and a vibration as an additional deterrent. The receiver is waterproof. Low battery indicator light lets you know when the battery need replacing. Instruction manual and DVD included covering installation and pet training. Testing tool allows you to test the operation of the receiver/collar.