The included seat belt tether attaches your dog's harness to the seat belt. The sturdy, rigid frame is easy to assemble & install. The strong, lightweight plastic panels lock together with no tools required. The special 9-inch high raised seat platform makes this a dog booster seat too. The safety seat supports furry friends up to 30 pounds so they can relax and sleep the miles away on the comfy quilted liner & cushion. The Seat protects your car's seat from pet hair & scratches.