Size: Bearing Inner Diameter: 21mm / * Inner Diameter: 6mm / * Wheel Diameter: 50mm / * Thickness: 18mm / * Axle Length: 36mm. Installation: Simple luggage rolls, without professional instructions, can be installed by yourself, very convenient. Also pay attention to the tightness of the wheel at the time of installation, so that the luggage rollers can roll better. Advantages: High quality aftermarket wheels. Durable, quiet, load-bearing, double bearing, flexible rotation. Load: a single suitcase can bear up to 51 kg, without deflection of the phenomenon for safe and reliable use. Cleaning: Replacement suitcase wheels are easy to clean and the wheels can be removed for cleaning. Buyers need to measure the data of the following suitcase wheels to find out what size they are able to roll: 1, measurement of the original outer diameter wheels (size 2, the inside of the measuring wheel groove width (width of the total installed width). < p> 3, through the length measuring screw (without