Specification Finish: Zinc plated Wheel: 254mm metal with Solid Tyre Min height: 680mm Max height: 890mm Extension: 210mm Outer Tube: 57.2mm Inner Tube: 50.80mm Centre of Bracket to Bottom : 410mm Features: Heavy-duty Material: This electric trailer jack is constructed with heavy-duty aluminum alloy material, durable and sturdy, providing you with quality service for years to come. Thanks to its robust construction and powerful motor. Broadened Wheels For Outdoor: 10-inch diameter trailer jack wheel can ensures excellent traction on any surface, featuring an automatic brake function for reliable safety. Convenient Operation: It is equipped with control handles. The height of the jockey wheel can be easily controlled by turning the lift handle. The forward and backward movement can be realized at your fingertips. Easy Installation: This trailer jockey wheel is equipped with a mounting bracket for convenient attachment to your trailer. It is widely used to move your caravan, boat trailer, or horse trailer, suitable for confined spaces, like yards, carports, driveways, caravan parks, etc. Note: The product cannot be used on a ramp greater than 5, dirt and gravel roads. Package: 1 x 10" Jockey Wheel 1set Mounting KIt(Universal fitting)