Fe-415, Fe-500, Fe-550, and Fe-600 are four different grades of TMT bars produced in India. These grade numbers signify the stress level that must be applied to make any deformation in the bar. More stronger and superior bars have higher grade. According to their strength and rigidity, the respective grades are given. Decorative structures like balcony railings etc are made with low graded bars, but for core building structures like roofs and floors high graded bars are used. Usually for residential constructions and homes, Fe – 415 is suitable whereas Fe – 600 bars are used for industrial use. For construction of bridges and underground structures, versatile bars like Fe – 500 and Fe – 550 are preferred.