Features: wear-resistant, silent, load-bearing, dual bearings, bendy rotation,Sliding is labor-saving, effortless and straightforward to use.Integrally molded, tougher and silence.Colour:blackMaterial:PolyurethaneSize:55x12mm, middle diameter: 6mmSize:50x12mm, middle diameter: 50mmPackage Contents:8 x Suitcase wheels/2 x Suitcase wheelsOnly the above equipment content, different merchandise will not be included.Note: Light mirrored image and various exhibits could cause the colour of the item in the picture just a little varied from the real thing. The size allowed error is +/- 1-3cm. Features: wear-resistant, silent, load-bearing, dual bearings, flexible rotation,Sliding is labor-saving, easy and simple to use.Integrally molded, more durable and silence.Colour:blackMaterial:PolyurethaneSize:55x12mm, center diameter: 6mmSize:50x12mm, middle diameter: 50mmPackage Contents:8 x Suitcase wheels/2 x Suitcase wheelsOnly the above kit content, different merchandise will not be included.Note: Light mirrored image and diversified reveals could cause the color of the item in the photo somewhat diverse from the real thing. The size allowed error is +/- 1-3cm.