Feature:1. 48PCS: The set includes 16PCS POM wheels, 16PCS spacer columns, and 16PCS hexagonal eccentric spacers, which is a very complete set of 3D printing accessories.2. GOOD STABILITY: Our pulleys are strictly designed and tested to make them work smoothly and stably; silent design, low friction, and durable bearings.3. WIDE APPLICATION: This 3D printer pulley can basically adapt to most 3D printers on the market, so you can use it with confidence.4. STAINLESS: This 3D printing wheel is different from the previous iron bearing 3D printer pulley, it is less prone to rust and has a longer service life.5. GOOD HELPER: This 3D printing wheel of ours has high printing accuracy, which can improve the printing speed very well and make your work more perfect.Specification:Item Type: 3D Printer Pulley Wheel SetMaterial: Precise steel and POMInner Diameter of Pulley: Approx. 5mm / 0.2inPulley Height: Approx. 10mm / 0.39inChute: Approx. 6mm / 0.24inOuter Diameter of Pulley: Approx. 24mm / 0.94inEccentric Spacer and Cylinder Inner Diameter: Approx. 5mm / 0.2inEccentric Spacer and Cylinder Height: Approx. 6mm / 0.24inProduct use: For 3D printers.Package List:16 x 3D Printer Pulley Wheel16 x Eccentric Spacer16 x Round ColumnNote:Note that there is a movable copper ring between the bearings. Ring movement is normal, otherwise the bearing cannot rotate. It's not a quality problem