These are pens that make the writing disappear when used with ZEBRA's red or green sheets. All are new and unopened. ZEBRA Check Pen α Blue P_WYT20_BL ✖️2 ZEBRA Check Pen α Green P_WYT20_G ✖️1 ZEBRA Check Pen Red ✖️1 Blue and green disappear with a red sheet, and red disappears with a green sheet. The regular price is 150 yen each. How about using them for exam preparation? #ZEBRA #ZEBRA Check Pen α #ZEBRA Check Pen