The Boat Lift U.S. Solar Lifts are available in 6K, 8K and 10K Capacities . Boat lift U.S. has developed a sealed, oil-bath gearbox™ specifically for boat lifts. This means that the gears never need lubrication allowing for a maintenance free drive system. This Solar Gear Box™ Boatlift comes standard with Leeson 12V Boat Lift motors, Custom made Fiberglass Battery Boxes with SS Hardware. Galvanized drive shaft, strong no-weld aluminum construction, and Aluminum bushings with grease fittings are standard. The grooved cable winders protect the drive shaft and helps keep the cables winding without overlapping. The Boat Lift U.S Gear Box™ Boat Lift also comes standard with Aluminum Bunks. All Boat Lift U.S Boatlifts are Manufactured to the Highest Quality. When choosing the proper weight capacity of a Boat Lift always keep in mind the total weight of your Boat (Wet Weight). Choosing a Boat Lift with a higher weight rating than you might currently need is a smart decision so you are not maxing out your new Boat Lift right from the start. This will also help if you are thinking about going to a larger boat in the future.