Fusion Suit

Samus Aran's Fusion Suit is her Power Suit's inner layer that was exposed to Metroid DNA. This caused this inner layer to change, to form the Fusion Suit. The suit has small claws on Samus' free arm, reminiscent of the Metroid teeth. The Fusion Suit, however, is very thin and has weaker shielding, hence dangerous to wear, and renders Samus vulnerable to cold. In the final battle of Metroid Fusion against an Omega Metroid, the SA-X and the Fusion Suit merge to create the Omega Fusion Suit. It's presumed that due to the removal of the Power Suit, the Fusion Suit was created by the Galactic Federation based of of Chozo design.