Angle steel commonly known as Angle iron, is perpendicular toeach other on both sides of the Angle shape of the long steel. There areequal-edge Angle steel and non-equal-edge Angle steel. The two sides of an equal-sided Angle are of equal width. Thespecification is expressed in millimeters of edge width × edge width × edgethickness. Such as "∟ 30 * 30 * 3", it indicates that the widthof 30 mm, while equal Angle steel thickness is 3 mm. Also available model, saidthe model is the number of centimeters wide, such as ∟ 3 #. The model number does not indicate thesize of different side thickness in the same model. Therefore, the side widthand side thickness of Angle steel shall be fully filled in in the contract andother documents, avoiding using the model number alone.