@scarfmace a submariners sweater traditionally is a white/off-white turtleneck. Think the u-boat captain in the first Indiana Jones movie.
Andersen-Andersen used to have specifically that, but I see they have rationalised their product line. So it would be this now:
https://andersen-andersen.com/collections/sailor-turtleneck/products/sailor-turtleneck-off-white






