The suit had a rigid interior and a 3-D knitted metallic exterior, providing protection from physical attacks as well as acid, heat, cold, most forms of energy, radiation, and electricity. A 3-D knitting pattern on a submolecular construction level gave the armor itself more strength, while allowing for the most comfortable suit interior. By expanding the field that keeps the armor rigid, the armor could encase itself in a protective force field that was effective against most forms of attack; Stark could also use this field to polarize the armor to either attract or repulse other items via magnetic polarity.