Pet Expert 50' Heavyweight Dog Trolley. This durable dog trolley is made from 1700 lb break-strength galvanized steel aircraft cable, coated with UV-protected clear vinyl for extended weather resistance. It includes everything needed for installation: 2 screw eye hooks, 1 spring, 2 rope clips, and 1 Lexan pulley. Designed for ease of use, the trolley comes with a down line and does not require an additional lead, making it ready to install and use right out of the box. Ideal for securely containing your dog while providing ample room to roam.