I'll post of the one I just played with and it looks interesting. Tried it on an ultralight with a couple of split shot on it just to see what it would do. It's not a floating jig, but it is super light. Ended up taking the split shot off and could still cast it, but very short casts, so my guess is it was designed for a fly rod but weighs less than 1/64 of an ounce. It does sink, but really slowly.
I'm on other forums that deal with the old turbo powered Buicks.;)