The Jansen Spectroscopes are a piece of headgear which can only be worn by Jan Jansen, a potential companion in Baldur's Gate II: Shadows of Amn and Baldur's Gate II: Enhanced Edition, as long as he has at least 17 Dexterity. It raises Disarm Traps and Find Traps by 25%, Detect Illusion by 20%,and they can be used once per day to detect invisible creatures. Jan has this item equipped when he joins the party.