Rollerball With Ultra-Smooth Tip For The Best Writing Experience. Line Width Approx. 0.6 Mm, Writing Colour Green, Waterproof According To Ink Standard Iso 14145-2. The Innovative Super-Flow-System Guarantees Consistent Ink Flow From Start To Finish. The Large Ink Reservoir Has A Level Indicator And Every Drop Of Ink Is Used. The Cap-Off Ink Does Not Run Dry Even If The Cap Is Removed For 2-3 Days. The One Business Has A Sturdy Metal Clip And An Ergonomically Rubberised Grip Zone That Provides A Secure Hold For Relaxed Writing.