Description: Quality Material: M4 Extruders are made of quality metal and PP, stable, and sturdy.Packing List: 2 Piece Synchronous Axis, 5 Piece Nuts, 1 Set Screws, 2 Piece Extrusion Gear, 1 Piece 3mm Pin, 1 Piece Timing Belt, 2 Piece Bearings, 1 Piece 5mm Pin, 2 Piece Buckles, 2 Piece Bearings, 1 Piece Air Connector, 1 Piece Spring + GasketEasy Installation: The 3D Printer Fastener set is easy to install and can directly replace old or damaged parts.Usage: Extruders have good performance, are convenient and practical, and are suitable for home and professional use.Portable: 3D Printer Parts are lightweight, portable, small in size, and easy to store and carry. Specification: Material: Metal PP Size Chart: Package Size: 9cmx13cmx2cm/3.54inchx5.12inchx0.79inch Package Includes: 2 Synchronizing Shafts5 Nuts1 Set Screws2 Extrusion Wheel1 3mm Pin1 Timing Belt2 Bearings1 5mm Pin2 Buckles2 Bearings1 Air Connector1 Spring+Gasket Note: 1. Please allow slightly error due to manual measurement.2. Due to the difference between different monitors, the picture may not reflect the actual color of the item.