Purchase Date: February 15, 2021 Purchased on Rakuten Set of 20: 1,599 yen (price at the time of purchase) I bought these for stock, but the whiteboard became unnecessary while I was using the ones I had before. Although I've opened the bag, they have been stored in a dark place and are unused. Below is the product description from Rakuten: High-Quality Whiteboard Markers, Set of 20, Medium Point, Round Tip, 4 Colors, for Professional Use, Dark Lines, Easy to Erase, Long-Lasting Ink, Suitable for Cram Schools, Classrooms, Tutorial Schools, English Schools, Schools, Culture Centers, Offices, Company Offices, Conference Rooms, Children's Lessons, Junior High Schools, High Schools, Universities, Kindergartens, and Nurseries, High Cost Performance, Free Shipping