Veevus 12/0 is a very thin thread without G.S.P. (Gel Spun Polyethylene). Its thin characteristic makes it good for medium dry flies and nymphs. Tests from Veevus show that it has a strength that is compared to 6/0 threads from its competitors.
Benecchi 12/0 = around 450g
veevus 12/0 = around 530g