[SECURE A 2/5 ACRE YARD: Electric Fence for 2 Dogs system is to keep your Pet safe and secure. Covers up to 2/5 acre including 328 feet of wire Additional wire can be purchased (Boundary Wire ASIN: B0DM632NGL) Expand to a 30-acre yard for gardens pools woodlands suburbs and more. Extra Add Receiver Collars Replacement ASIN for Wired Pet Fence: B0D4LRY547 ADJUSTABLE BOUNDARY RANGE: The Transmitter has a 0-9 level adjustable boundary design you can adjust the boundary range through the "+" "-" on the controller according to your own needs to ensure that your dog stays in the designated safe area. 2 LEVELS OF STATIC CORRECTION: The receiver collar has 2 modes when the dog is close to the boundary line the receiver indicator light is green and an automatic tone alarm sounds. If the dog does not leave it will send a 10-second circular static correction at level 2-3 Make your pet to return to a safe area. IP68 WATERPROOF LEVEL: Underground 2 Dog Fence System Receiver 2 Collars uses IP68 waterproof technology and can be worn for swimming without affecting signal transmission. (Be careful not to exceed 10 minutes underwater). There are 2 collars inside the packaging. "SUITABLE FOR MOST PETS: In-Ground Pet Fence Suitable for dogs 9 months old Suitable for pets weighing 20-120 pounds the size of the pet collar can be adjusted from 8-26 inches Please confirm your pets weight when purchasing and neck size."]