The part that protruded down from the cap along the side of the pen to form the “pocket clip” fit between the gear teeth and made turning easier & more reliable - you slid the cassette down the body of the pen until that part engaged the teeth. Later I came to prefer the style of pen below due to the flatter protrusion, but both worked pretty well.
The part that protruded down from the cap along the side of the pen to form the “pocket clip” fit between the gear teeth and made turning easier & more reliable - you slid the cassette down the body of the pen until that part engaged the teeth. Later I came to prefer the style of pen below due to the flatter protrusion, but both worked pretty well.