It looks like they used a standard cheap foam casting material of the time hence it has a certain life expectancy if not looked after correctly.
Both the heel and soles were foam casted pieces and painted with zolatone paint.
It looks like its been exposed to the elements too many times.
Same thing has occured on many nike shoes of similar ages where similar foam is on midsoles.
I hope the other prop pairs are still there!
Cheap or expensive, it doesn't matter. The point is, the polyurethane foams that they used back then only lasted 5 or 6 years before they crumbled. Both my first pair of NIKE AIR PRESSURE and my REEBOK PUMPS did the exact same thing after about 5 years.
In one of Tiffany Beers recent videos, she talks about storage for "your keepers" and she uses clear stackable plastic containers for all her low tops. She says that mids and highs won't fit, so she suggests the big zip lock bags.
I want to know, it is the chemicals in the air (oxygen, oxidises things) or the UV in light that destroys the materials? If it UV, then you want black storage tubs,, not clear. Or a dark room with no windows like I have, thanks to it being a home cinema.
Tinker has called them Air Mag's though he says they aren't Air Mags, he has still called them that.
If you look at the diagram explaining the different parts of the MAGs, you see "glowing air bag", so the shoes were most definitely supposed to have air bags, and ones that glowed.
EL must have been really new tech at the time and they use it because it provides a uniform colour and does not hot spot when captured in images.
They cut the EL to represent the glowing air bag, but it ended up being recognised as shoes with lights.
The MAG part is of course magnetic and was supposed to allow him to walk up walls and even hang from a ceiling. Due to tech limits of the time and budget restraints, the scenes showing this did not get shot.
So the name "AIR MAG", is correct "from a certain point of view"