Permanent floating filter, by Finum brand.
Made of black plastic, it works for both teapots and cups.
Any type of spices can be deposited in the floating filter and added to the beverage of your choice (tea, coffee, wine, etc). You can use any spice like nutmeg, cinnamon, etc.
Its raised lid makes it easy to remove from any hot beverage as the filter and lid do not separate in this process. Once the infusion is finished, the lid can be used as a plate to put the filter and avoid dripping.