【Set Includes】4 pieces of window silent nylon pulley slot wheel sliding door fittings. Suitable for windows and doors. 【Sturdy Material】The window pulley is made of quality iron shell and nylon wheel, sturdy and wear resistant. 【Single Wheel Pulley】Single wheel pulley design rolls smoothly, operates silently with low noise. Metal axle window pulley is easy to push and pull. 【Easy To Install】Easy to install and assemble. Stable structure helps prevent loosening. 【Application】Door rollers are widely used for sliding doors, windows, cabinets, and more. Specification: Material: Iron, Nylon Size: 75mm x 17mm x 4mm / 2.95 inch x 0.67 inch x 0.16 inch Package Includes: 4 pieces sliding door window pulley Note: Please allow slight variations due to manual measurement and differences in display monitors.