Hydraulic fluid by Bilstein?

[Michael Murphy <mmurphy@nais.com>]

Dear list,
Was at local parts place (that's attached to used foreign auto sales
where a '90 V8 is still for sale) getting cooling hoses and saw a can of
Pentosin on parts shelf.  Queried the guy about what they use in Audi's
(the never-ending search for a local source of <$20 hyd. fluid).

He shows me a blue bottle of Bilstein Febi Hydraulic Mineral Oil
(all German writing). Bottle is marked 2615 and is specified as
ZH-M spec fluid.  At $8.50/liter, he says that's all they use in
Audi's.  Though grasp of German is miniscule, it appears to be mineral
based, not synth.  Anyone ever here of/use/recommend this stuff?
TIA,
MJ Murphy