Curtain rail pulley: You will receive 20 curtain track pulleys of the same size. The wheel diameter is 14.5mm and the outer diameter is 17.5mm, which is suitable for curtain rails with a rail width of 18-23mm. Installation is simple: it you just need to insert the pin hook into the eyelet at the bottom of the bracket. For curtains with holes or loops in the back, simply add hooks. The crawler wheels are smooth and not blocked. Scope of application: It can be installed in the windows of your living room, study, bedroom, office, piano room, dining room, and you can easily draw the curtains to make every morning beautiful.Noiseless Design: The silent double-layer design of the running rail, the pulley will produce the least noise when pulling the curtains. When you get up in the morning and open the curtains, you can't hear the harsh sound. Stable Material: Made of plastic and stainless steel, durable and not easy to rust, with super load-bearing capacity, all the curtains can roll and slide smoothly on the rail.Quantity delivered: 20 pieces Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.