From the publisher's website:
Visualize your spoils in the Kingmaker Adventure Path with this thrilling new assortment of 54 unique GameMastery Item Cards. From strange fey treasures to the regalia of kings and curiosities from ancient empires, the exotic items in this set add a delightful dimension to any Item Card collection and bring a great sense of immersion to any fantasy campaign!
GameMastery Item Cards allow heroes to keep track of their equipment in style, and the set is completely compatible with all of Paizo's other GameMastery Item Card sets. Each of these full-color cards features a beautiful portrait of an item on one side with space on the back to keep notes. GameMastery Item Cards are compatible with any fantasy roleplaying game.