This is the engine room of the pen. Since you source premium JoWo #6 components but machine the housing ourselves, the terms should highlight that seamless transition.
• Grip Section (or simply "The Section"): The precisely contoured part where the writer's fingers rest.
• Section Thread: The 0.05mm tolerance threads that screw the section directly into the barrel.
• Nib Unit: The combined pre-manufactured assembly consisting of the JoWo duotone #6 steel or gold nib (the writing point) and the feed (the black finned ink-regulator).
• Reservoir Interface: The secure internal seat where the Schmidt K5 converter snaps into place.