Hi,

I am looking  for  some bladder tubing like what's used in this video https://www.youtube.com/watch?v=QzzxGEHc1N0

at 14:16 you can see them removing what looks like the bladder from inside the rim. It looks like a simiolar material to vacuum bagging  membrane.

Any ideas?  It needs to be a lightweight thin material, not like silicone, due to the application i want to use it for.

Thanks