Cat or Feline School Gear is a witcher armor and swords set inspired by the School of the Cat for witchers. It's one of the Scavenger Hunts in The Witcher 3: Wild Hunt. The set includes chest armor, steel and silver swords, crossbow, gauntlets, boots, and trousers, all of which are upgradeable except the crossbow. Also, there is not a New Game + version of the crossbow.
The armor set is worn by Gaetan in the DLC quest Where the Cat and Wolf Play..., as well as presumably being worn by Kiyan before he was experimented on by a mage. According to said mage's notes, the gear used by witchers of the School of the Cat is heavily inspired by elven weapons and armor.