Aluminum Square Tube                                              Aluminum Square Tube has sharp corners both inside and outside. It is commonly produced in both 6063 and 6061 alloys. The 6063 is generally produced in lighter thicknesses than the 6061 and used in cosmetic and light structural applications. 6061 Aluminum Tube is produced in heavier wall thicknesses and provides approximately the same strength as mild steel and can be used for heavy duty structural applications. Tubes come in mill finish and clear anodized. See product page for details.