Frixion Ball Knock Zone - Green Inspiration Green / Black Ink Product Code: LFBKZ-3SEF-IG This is a truly complete package. Utterly inspiring. Good writing feel, less ink clogging, and the ink lasts a decent amount of time. All the fatal flaws of Frixion have been resolved. Despite having characteristics close to flaws, Frixion became too widespread. Pilot had a responsibility to society to improve this series. This is the answer. An overwhelming answer. It's at a level where you could use it for official documents (but don't). No exaggeration. I wholeheartedly recommend it.