For those who like the Zebra Sarasa gel but prefer a bolder line -- the Zebra Sarasa Bold with a 1.0 mm tip.

The Sarasa Bold is a retractable gel ink pen which uses water-based pigment gel ink. The ink is acid-free and archival quality as well as being smooth and free-flowing. The see-through barrel allows you to see the ink supply so you know when you're running low. The barrel has a soft rubber grip for comfortable writing. The pen color matches the ink color. These pens have a broad point (1.0 mm) and are available in three (3) colors Black, Blue and Red.