Color: Black Material: Rubber Metal Bearing Diameter: 21mm Internal Bearing Diameter: 6mm Wheel Diameter: 50mm Wheel Thickness: 18mm Shaft Length: 35mm Installation: A simple luggage roller, without professional advice, can be installed by yourself, which is very convenient Pay attention to the tightness of the wheels during installation, so that the luggage casters can roll better Advantages: High-quality spare wheels Strong, quiet, load-bearing , double bearings, smooth rotation & nbsp; : a single suitcase can load up to 51 kg without deviation, and it is safe and reliable to use Cleaning: The luggage replacement wheels are easy to clean, and the wheels can be removed and cleaned