Pre-War Formalwear is a rare Artifact — Equipment card from Fallout (PIP), collector number 369. Current market price: $3.11 (foil $3.27), TCGplayer market prices via Scryfall.
When this Equipment enters, return target creature card with mana value 3 or less from your graveyard to the battlefield and attach this Equipment to it. Equipped creature gets +2/+2 and has vigilance. Equip {3}