The Pentel Wow! Gel Pen features a unique triangular-shaped barrel & grip that makes it easy to hold and keeps pen from rolling off desks. Permanent, waterproof, fade-proof and acid-free ink for a lasting impression. Maximum comfort and control with the latex-free grip. Click top to advance tip; click side button to retract. 0. 7mm tip writes medium lines. It is covered by pentel’s exclusive limited lifetime .