The RocknRoller® Multi-Cart® R16 and R18 Groundgliders feature 3-inch-wide no-flat wheels and casters to easily transport heavy equipment over grass, dirt, sand, rough concrete, and thick carpets. Groundgliders feature a 25 percent larger steel tube on the frame bed and foldable handles for significantly added structural strength. The R16 has 6-by-3-inch front casters, 8-by-3-inch rear wheels, and a frame that extends to 52 inches in length and retracts to 34 inches for storage. The carts transform into any of eight configurations to accommodate innumerable cargo types. They have expandable frames to carry large loads and fold up small enough to fit in trucks or vans.