Originally Posted by
Chombi
The cells on the foam were definitely open. That's why it had that rough looking (but soft) grippy texture on the surface. Pretty much like a sponge.
I still remember squeezing out water from them to dry them out when I got caught out in the rain.....
Chombi
Well, I actually went to their website (still in business and they've expanded) and learned that they say: "Foam Tubing Materials We Work With:
Grab On uses some of the finest
closed cell foam tubing..."
but they don't use neoprene, they use either Nitrile (NPVC) or EPDM...but they say that they use high-speed grinding to shape the materials, that would expose at least a layer of closed cells on the surface. I imagine that break-down as the material ages might also make the closed cells become more "open" but not really sure...foam "rubber" isn't a material I've studied much.