Astro 5A?

This is the description:

Astro: one sliding die, with a small object that weighs close to nothing tied to the string. this makes traditional 5A tricks possible, that are sometime impossible with DD, due to the weight diference, but also alowing some Sliding counterweight trick.

Does someone here have a video on it?
playing astro 5A?

And another.

If people say 50/50 string (50% Hybrid/50% Polyester), is there a sewing thread that 100% cotton?
or they use something a unique and different kind of cotton to use for making hybrid threads?, because I’m searching here one, and i don’t find any 100% cotton sewing thread.

David Mellons is a great Double Die / Astro 5a player.

Jump to 1:30 for Double Die / Astro 5a play.

There is thread that is 50/50 blend, and there is threat that is 100C and also 100P and even 60Nylon 40Poly. 
Head to a Micheal or JoAnns and look at the thread.  Even a Walmart has alot of options.

I even found a spool of 6 pre-twisted 100% cotton, all I had to do was spin it and fold.

Tyler Severance Worlds '07 1st

Astro at 1:40

Here is the ultimate 5a post. Down at the bottom there are three “pure freehand” I think the first one has astro 5a in it.

Hope this helps.