A limited acro drive commemorating the 100th anniversary of pilots. Gift box is also special A high-quality oil-based ballpoint pen with acro ink that has been designed to emphasize the smoothness of an acro ink and the shape of the clip. The surface of the metal body has a matte finish that gives it a smooth feel when you squeeze it. The knock system uses a "rotate-out" mechanism. Prevents accidental knocking and ink leaking. It also has a smooth tactile feel when rotating, and it stops when the ball is released.