It's 125 micron
This is corect.
I got mixed up with 135/36 ;-)

If Ilford was using the same base for their 3200 Rollfilm it could be because this product has only limited shelve life.
If you roll 125 micron triacetate wthout anti curling layer on the backside onto a 120 core and keep it wound for over a year you expirience terrible curl of the film after development. At least thatīs the expirience we have.
With the 3200 ASA product this either might not have occured because of a fast supply chain or because Ilford uses a kind of double sided substrated TAC with NC on both formats. If this was obtainable (double side substrated TAC) it could actually be something interesting to look at for future small volume runs. For Silvermax this option did not exist as the old stock base we used up was only substrated on one side.

Some of you people really have very deep inside knowledge.
Itīs a pleasure to hang out here but now I have Photokina meetings again ;-)

Mirko

PS 1.000 rolls of Silvermax have been sold the past 3 days. Now we are almost out. We limit sales now to 1 roll per person at the trade show booth.