Plastic Hinge for 20x20 Aluminum Extrusion : ID 1215 : $0.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Adjustable Angle Support for 2020 Aluminum Extrusion : ID 1257 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits
20-2020 | 20mm X 20mm T-Slotted Profile - Four Open T-Slots
Aluminum Extrusion Corner Brace Support (for 20x20) : ID 1155 : $0.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Amazon.com: V-Slot 2020 Extrusion, Linear Rail 500mm (4pcs). T Slot Aluminum Extrusion for Framing, with V Type Slot Upgrade for 3D Printer Parts, CNC Rail, Linear Motion Slide Rails (Black 20x20 Extrusions) :
Aluminum Extrusion Double Corner Brace Support (for 20x20) : ID 1259 : $1.95 : Adafruit Industries, Unique & fun DIY electronics and kits
150mm T Slot 20x20 Aluminum Extrusion European Standard Silver Extruded Aluminum Anodized Linear Rail High Strength Guide Frame for 3D Printer Parts and CNC DIY Workbench(4 PCS,5.9 Inches): Amazon.com: Industrial & Scientific
Part Number | 20x20 Aluminum Extrusion - 5 Series, Base 20, Two Adjacent Closed Sides | MISUMI | MISUMI
250mm T Slot 20x20 Aluminum Extrusion European Standard Silver Extruded Aluminum Anodized Linear Rail High Strength Guide Frame for 3D Printer Parts and CNC DIY Workbench(4 PCS 9.85Inch): Amazon.com: Industrial & Scientific