NX bottle Nut size?

does anyone know the size of this nut, i know its different from the NOS one. i think its 6AN??? i need one, anyone know any part numbers ?

PN: 11703

i saw that nut, but is that the one i need to hook up my 4an main line to the bottle???

i need the one that reduces the size of the bottle openning to the main line which is a 4an.

your best bet is to call nx and find out exactly what u need