Copic Ciao storage 36×2 Slots.
The hole size is 14mm in diameter and 120mm deep.
Pens smaller than 14mm in diameter can be used.
It can be used either standing up or lying down.
I would be happy if you could upload it on SNS etc.
Copic Ciao 36 color → https://amzn.to/3v7FvKe
72 color → https://amzn.to/3P6HfKI