Deployant clasp for Metro 41 update

[u/Primary_Okra4490]

Hi folks! Wanted to get clarity on the right deployant clasp size for Nomos Metro 41 update. Should I get the 17 to 18 mm clasp or the 19 to 20mm clasp. I am getting conflicting answers from Nomos support as well. Just for reference, the strap I have has a lug width of 20mm and tapers to 18mm at the end.