What is T-Slot Aluminum Framing, and How do Engineers Use It?

They make bars that you put in the t-slot part that you can use 1 rails into a 2000mm rail for my Y axis IMG_×2448

Im not sure of any companies or products, but a quick google search on aluminum extrusion pieces and parts, will give you a good cheap start to

aluminum slot wheels 2PCS 20 Series T Slot 2080 Aluminum Extrusion Profile '',European Standard Anodized Linear Rail for 3D Printer Parts and CNC DIY 400mm Silver

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