Using this PetSafe Indoor Instant Wireless Pet Barrier is a breeze. First, place the barrier near the area you want your pet to avoid. Make sure to put fresh batteries in the transmitter (3 x AA, not included) and the receiver collar (2 x 3 Volt lithium, included). Adjust the collar to fit your pet's neck, which should be between 15 - 71 cm. When your pet enters the restricted area, they'll first hear tones and then feel a safe static stimulation. Remember, the system has an over - stimulation protection that stops the stimulation after 15 seconds. For multiple pets or more protected areas, you can add as many barriers and collars as you need. Keep the receiver collar dry as it's only lightweight and waterproof, not suitable for deep water. Regularly check the batteries to ensure the system works properly. If you have any questions, don't hesitate to contact our customer service.