Necessary pen inks for blue pen, with 2 pieces in a case.

• Metal necessary ink made of brass for excellent pen balance.
• Iridium nozzle that protects the ink from leaks, ensuring smooth writing and comfort.
• Ink resistant to light, water, and chemicals.
• Writing length: 4500m (equivalent to at least 4 standard pens).
• Tip thickness: 0.8mm.