groove special big mac refill automatically disappears large capacity fading calligraphy practice board special refill

Automatic Fading Pen Ink

For special use in calligraphy practice sheets, dedicated groove calligraphy practice sheets

Writing Thickness: 0.5 MM; Writing Color: Blue; Pen Tip Type: Bullet Tip

This product is suitable for students to practice calligraphy, do draft exercises, and children to draw. The handwriting begins to fade after about twenty minutes, and disappears completely after a few hours without leaving any trace, without affecting future writing!

This product is [high-efficiency][environmentally friendly]!The fading rate is related to weather, temperature, and humidity