I'm trying to make sense of the X/0 sizing for thread versus the denier sizing method. I have Uni's Big B thread, which I believe is a 40 denier, and I'm wondering how it compares to 6/0 Uni. It looks like it's about twice the size of 6/0 and actually makes really strong furled leaders. Can anyone help me get my head around this? Simple minds want to know.