My dad recently bought a pencil to go with his pen and fountain pen. Most pencils from this style I've seen have been the twist kind that you pull apart and use the eraser that is inside. The one he got is different in that it has a Parker Lead Cartridge in it and you unscrew this pencil rather than pull apart. My question is...where's the eraser? I can't imagine a pencil without an eraser. The top of the lead cartridge has a plastic black sort of star shaped piece with a (looks like) stainless steel ball bearing in it. No place for an eraser. Am I missing something here? I can't imagine a person unscrewing a pencil everytime they need to erase something. Susan