MUJI's Smooth-Writing Gel Ink Ballpoint Pen Knock Type 10-Color Set 0.5mm Made in Japan. It seems the set is no longer sold. I am selling these because I no longer use them. The transparent case has many scratches. Black, Red, and Yellow have been used, and Black especially shows signs of use. The other 7 colors, some with the ballpoint tips still intact, are unused. Please check the ink levels in the second image. Also, the Black and Red pens have ZEEBRA SARASA refills. If you wish, I will include two free Black refills.