Do you also have too many ink bottles? Keep track of them all with Tsubame's Ink Collection Card! Simply fill the empty ink bottle on the card, and then write down the brand, the name of the ink, and any properties. This is also a great way to keep track of which ink is in which pen. Each card contains two squares, four rows, and an ink bottle. Each box contains 150 cards measuring 91 x 55 mm.