Color: Fluorescent Green. Ink: Biopolymer Ink. Mechanism: Slide Lever Mechanism. Water-based Pigment Ink. Tip Size: 0.4mm. Line Width: 0.3mm.The Hi-Tec C Coleto is a highly enjoyable pen where you can "choose" both the body and the refill according to your preference.The options for customization are endless! You can create your own original Hi-Tec C. It provides a smooth writing experience without smudging, despite its fine tip.With Pilot's unique "4-point support system" pipe tip and biopolymer ink, it allows for thin, non-smudging, and smooth handwriting.The process of selecting a Hi-Tec C Coleto is as follows: 1. Choose the body (sold separately). 2. Choose the refill. 3. Set them together, and your personalized Hi-Tec C Coleto is complete! Setting or replacing the refill is incredibly easy. 1. Open the cap at the top of the pen. 2. Insert the refill in your preferred color. Done! Both setting and replacing are very straightforward.