Hello,I am searching for orings for my Fx impact and i found almost all on one German web shop ( where i am living for most of the year) but there are no way that I can find this 2: 2,9x1,78 PUR 90 2,84x2,62 PUR 90 I mean i found those but in NBR 90 but not in PUR 90. Can somebody tell me ist so...