4Pcs 12mm x 1040mm Linear Rod, Coavoo Diameter 12mm Case Hardened Chrome Plated Smooth Linear Motion Rod Shaft Guide Rail - Metric h8 Tolerance L The case hardness could be reach to 58-64 HRC., Durable and corrosion-resistant Humanization Design: Chamfer on both ends, easier to install linear bearings and won't hurt fingers when installing it 4pcs Diameter 12mm x 1040mm chrome linear shaft steel straight smooth sturdy rod bar, Length (0., 47 x 40., 94) 1040mm Steel Rod 12mm X 100mm Linear Rail Rod Shaft For 3D Printer & Ghana 12mm Chrome Rod 4Pcs Diameter 12mm chrome linear shaft steel smooth rod L: 40.94 inch /1040mm We could provide all the customization: any length, threading, and other end processing, you could get some information from pic 2, if you have needs, please message us, thank you We could provide all the customization: any length, threading, and other end processing, you could get some information from pic 5, if you have needs, please message us - We can process the end of the rail as you need, some examples you can see the image 4 Linear Motion Shaft Guide Kit Set, 4Pcs 12mm X 1040mm We can customise the linear rail, including the length and finishing.