Packing: 4pcs Material: stainless steel + nylon Size: 16mm(0.63in)x64mm(2.52in), wheel width 8.3mm(0.32in) Fixed with stainless steel rivets, firm and non-corrosive, strong load-bearing capacity It is durable, wear-resistant, easy to install: easy to install and assemble, stable structure, not easy to loose Wheel can swing self-adjustment Widely used in sliding doors, windows, cabinets, etc.