The Leather Breastplate is a light armor in Final Fantasy XII that boosts the wearer's defense by 6 and HP by 30. It is the third weakest light armor in the game and basic equipment.
The Leather Breastplate is sold for 300 gil in Rabanastre after Barheim Passage, Dalmasca Westersand after the Leviathan but before getting the Treaty-Blade, Barheim Passage before obtaining Treaty-Blade, Nalbina Fortress, Bhujerba, and Dreadnought Leviathan.
It is rarely stolen from the Wildsnake, and is made in the "Assorted Leathers" set in the bazaar by selling two Wolf Pelts (from wolves and hyenas), one Tanned Hide (from various enemies, e.g. Slaven), and two Dark Stones (from the undead, e.g. the ones that spawn in the Barheim Passage when the lights go out).
The Leather Breastplate is sold for 300 gil in the Barheim Passage, and in Rabanastre and Nalbina Fortress after escaping from Barheim Passage. It is found as a treasure in the Garamsythe Waterway's East Waterway Control (80% chance to appear, 40% chance for gil, 50% chance the item treasure is the Leather Breastplate without the Diamond Armlet equipped), as well as in the Trial Mode Stage 3 with the Diamond Armlet equipped.
It is still the rare steal from the Wildsnake and is made in the bazaar set "Assorted Leathers" with the same items as before.
The Leather Breastplate is the third weakest light armor, giving small amount defense and 30 HP.
In the original version, Balthier and Fran start with the license for it, Light Armor 2. In the Zodiac versions, Machinist, Monk, Archer, and Shikari can equip it, and Balthier and Fran still start with the license for it.
Vaan starts with the inferior Leather Clothing, and so it may be beneficial to procure a Leather Breastplate early from the Trial Mode for him in The Zodiac Age versions where Trial Mode spoils can be brought back to the main game. Getting three this way would also allow the player to upgrade Balthier and Fran's equipment as soon as they join, as they already have the license for it.