What is the name of the furry membrane between the good bit and the shell?

And how can I cook them so it comes off easily. I've bought some (Chinese)
but when I roast them (in the oven as open fires were a thing of my past),
the membrane does not come off. I am sure it used to in the good old days
when we peeled very hot chestnuts in front of the fire, and I do not recall
treating the chestnuts before roasting. Online there is much talk of
soaking/simmering/boiling them first.

Anyone had actual (not theoretical) success with Chinese chestnuts, and if
so, how?

TIA,
Bill