I have been trying to get information on a Sinn 810 Q HYDRO I traded for you can see the thread here:
Info Sinn 810 Q HYDRO Was it the first HYDRO?
On your thread here you talk about a Sinn Hydro prototype in 1990 I believe my watch is from 1994 or 1995 as it looks like the one from the 94 Sinn catalog and the back is stamped
C-92201 with
HYDRO below it but it still has on the back case 20ATM/200M I know the HYDRO was rated at 8000M so I assume this is a early model that just does not reflect the 8000M yet.
On the link bellow there is a Interview with Carlos Rosillo from Bell & Ross where he says they have the
patent on the Hydro system: use of liquid silicon in the watch case for perfect water-tightness and perfect readability. Yet they did not make the Hydro Challenger until 1997 which means the Sinn 810 Q HYDRO came first, right?
Interview with Carlos Rosillo if you want to read it:
http://www.timezone.com/library/tzints/tzints0013
I was also told this watch was owned by a former Sinn employee and it looks like the last time the battery was changed the oil was not replaced. I'm going to send it in to Sinn for a full service with oil change, sounds like an automobile doesn't it.
Now that was a mouth full
Kevin