You have to know who the Mfg. of the blades are to know size correct on some sizes, like #0 at one place is #00 at the other.

Blakemore uses a #0 on their 1/32 Oz heads and I believe a #1 on the 1/16 Oz heads The main thing is you don't want the blade so large it turns the jig round and round. They also use a #2 Split ring on the 3 sizes I have, 1/32, 1/16 & 1/8 oz. I use the same size, but I do also have some #1 size that I like, but not necessary. For sure I do not ever use a smaller one that that as I see no reason to do that. Oh and I do believe for the 1/8 you can go to a #2, but I have some Willow Leaf #2's and boy they are large, but it will work.

Oh one other thing, if I am using a 1/32 Oz Pony head which in reality weighs in at 1/24 Oz I use a #1 Willow Leaf blade and probably only if I use a Willow Leaf blade.

I do find the Pony heads great, but a bit funny since the weight on the small ones is off, but the 1/16 is very close!

Skip