Also known as: 破裏拳ポリマー
破裏拳ポリマー / Hurricane Polymer / Hurricane Polimar / Hurricane Polymar
1974 anime by Tatsunoko. One of their "superhero series", together with Gatchaman, Casshern and Tekkaman.
When the protagonist dons his helmet, it wraps his body with a special polymer that forms an almost indestructible suit and gives him various powers.