I've seen people hunt with a single stand but only on a pfs witch is what I intend to do. I think but am not 100 percent sure that the number represents the size, IE 1745 would be 1.7 mm internal size and 4.5 mm outer diameter and 1842 would be 1.8 mm internal and 4.2 mm external, which would suggest the 1842 would have a thinner wall were as the 1745 is the heavier tube, on my tube catty,s the size of the loop makes all the difference, full length doubles fire 12 mm lead a treat were as a third length loop is better for 9.5 mm steels, hope all that makes some sensemakes perfect sense thanks