The Ennso Piuma looks to me like a large Fisher Space Pen, but I like the concept of the wide cap threads.
The interchangeable nib system screws inside the pen grip and resides a couple of millimeters in to create a unibody appearance. The cap threads are wider and allow a fast opening and closing of the pen. In addition, a milimetric-rounded gap defines the connection between the cap and the body.
fountain pen users 