The Rolin Manufacturing stack mover comes in 11ft , 13 ft or 15 ft widths with an optional 2' extension available. Lengths availabe range from 25 to 32 feet. Models are available in 8 to 14 ton capacities. It comes with your choice of 2 heavy duty hudraulic motors or P.T.O. driven gear box at 540 or 1000 R.P.M. It is made of heavy duty structural tubing making it the most rugged and durable mover on the market. It follows the tractor tire wheels, making it easier to pull and weigh on scales. Chains can easily be adjusted by loosening 3 bolts, turning the eccentric with a wrench and retightening the bolts.