VEVOR 2PCS Linear Motion Rod, 20 mm x 1200 mm (0.79 x 47.24 in), SFC20 Carbon Steel Linear Rod Shaft, Anti Rust and High Precision, High Hardness Shaft, for Cutting Grinding Milling Drilling Machine Complete Linear Motion Rod Shaft Kit High Precision, No Deviation Smooth & Silent Operation Broad Compatibility Multiple Sizes Available Deformation-Resistant Design Rail Length: 47.24 in/1200 mm,Straightness: 5 mΩ/100 mm,Shaft Type: SFC20,Item Model Number: SFC20-1200L-1,Quantity: 2 pcs,Surface Finish: 0.1–0.22 μm,Material: High Carbon Steel & Aluminum,Diameter: Ø 0.79 in/20 mm