The Noldor, Goldberry, Eowyn, and Laurelin Models all utilize reverse threading. What this means for you is that when you to open refill the pen it unscrews the opposite direction than you’d normally open your section! For the Noldor/Eowyn models it is employed in order to keep the section from opening when you grab the body and intend to open the cap. For the Laurelin model the same thing applies but if that section were to unscrew instead of the cap the section would become stuck in the cap, making the reverse threading even more vital.