The distinctive stormtrooper armor donned by Captain Phasma of the First Order was unique to her. Phasma's armor was distinguished by its chromium polish, which came from a salvaged Naboo yacht once owned by Emperor Palpatine of the Galactic Empire, the predecessor to the First Order.
Although the chromium finish offered some radiation shielding, Phasma's main reason for wearing it was to represent past dominance. Phasma complemented her armor with a standard First Order armorweave cape. Her armor's gauntlets were specially modified and expertly engineered for crushing. Phasma asserted that her armor was so strong that even a Wookiee, known for their ability to tear off limbs with ease, could not crush it. However, when faced with a threat, she chose to surrender rather than test the validity of her claim. Furthermore, her armor could withstand blaster fire, as demonstrated when Rose Tico's attempt to kill her with an SE-44C blaster pistol was unsuccessful.
Due to the late inclusion of the character in The Force Awakens, Phasma's armor was constructed from steel. For The Last Jedi, Michael Kaplan, the costume designer, and his team had sufficient time to apply silver plating to the costume.