Sufficient Quantity: Package includes 20 extruder wheels, enough to meet your various needs and replacements. Check Dimensions: Each 36-tooth gear measures approx. 11 x 11 mm / 0.43 x 0.43 inches (L x W), its inner diameter is approx. 5 mm / 0.2 inches, 36 teeth, suitable for most standard 3D printers; please verify size compatibility before purchasing. Practical Function: These 3D printer parts can replace your broken ones, making your printer more efficient and improving the performance and reliability of your 3D printers. Good Load-Bearing Capacity: The 36-tooth gears are made of high-quality stainless steel, rust and corrosion-resistant, durable and stable to use, with good load-bearing capacity, improving the working efficiency of your printers. Wide Compatibility: Our stainless steel extruder wheels are easy to install, compatible with -10, -10S, S4, S5, 3, 3 Pro, and most 3D printers.