To distinguish between sets of 2 and 3 keys, we use "dango" (rice dumplings) and "sakuranbo" (cherries) ^ - ^ These are also very helpful during trial lessons! ・Dango x 4 sheets, Cherries x 4 sheets (8 sheets total) ・Laminated! They can be stood up on the keys, so they won't get in the way! They can be used repeatedly ♪