Before using the dollies, it's crucial to attach the provided circular non - slip pad to the center of the dolly's top plate. This simple step ensures that objects remain stable and don't slip while being moved.The Furniture Lifter is designed with user - friendly features. It has two lengths: 13" before assembly, offering a 1/3.5 effort - saving ratio, and 24" after assembly, with an even more impressive 1/6.5 effort - saving ratio. The Connectable Dollies, measuring 4 3/4"x4 3/4"x 2", are individually strong with a 165 - LB load capacity each. When combined as a set of 4, they can handle a total load of 660 LB.In terms of material, we've used a combination of ABS, Steel, and TPE. This blend not only guarantees durability but also provides the necessary strength for heavy - duty tasks. The 1.25" small casters with TPE wheels are a highlight. They are impact - resistant and wear - resistant, and most importantly, they won't leave any scratches on your floors, making them suitable for use in various environments.Whether you're a professional mover or a homeowner looking to rearrange furniture, our product is up to the task. It can be used to move and lift heavy items such as cabinets, chests of drawers, crates, furniture, or appliances. It's perfect for use in homes, warehouses, shops, and garages, offering a convenient and reliable solution for all your heavy - object - moving needs. Material: Acrylonitrile Butadiene Styrene (ABS).