What do you mean define how it works? An Organic Exoskeleton is an organic steel substance that is stronger than any earth metal. In this form he can withstand extremely high temperatures of heat, punishingly low temperatures, and electricity. Impacts, long falls(they still hurt him, depending on the height and strength of his attack or whatever he got hit by) Artillery fire and other types of round.

it's a metal that forms around his body, have you not seen Colossus?