Hook: Wall Medium (Blue Square)The Art: Kaas City decoration fits into a blue medium square wall hook.
Hook: Wall Large (Purple Rectangle)The Art: Kaas City decoration fits into a large purple rectangle wall hook.
How to Get an Art: Kaas City Decoration
Cartel Market Decorations
The Art: Kaas City deco is part of the The Arneclin Masterpieces, a set of decorations that you can buy directly from the Cartel Market with Cartel Coins. All decorations from the cartel market, including the Art: Kaas City deco, can usually be found on the Galactic Trade Network (GTN) and bought from other players with credits.
If you're looking to get an Art: Kaas City, the easiest way to get it is to head to the Galactic Trade Network (GTN) in SWTOR and buy it with credits from another player. You can also buy the full The Arneclin Masterpieces from the cartel market or GTN, which includes this deco and a few others that match.