Magneto's Helmet has been built to protect the latter from psychic attacks or mind-reading from telephatic mutants and other superhumans.
X-Men TrilogyThe helmet is used by Magneto to block Xavier's powers from reaching into his brain. The same design for the helmet is used in all three films from the original trilogy. Sebastian Shaw to protect him from Charles' powers, Magneto stole the helmet from Shaw during the climatic battle at the end of the film. Later on, after escaping with his team of mutants and recruiting Emma Frost, Erik sports a scarlet and purple colored helmet, with a detail added at the center of the forehead.