Anyone changed these before?
The nut holding it on is like 3 thin nuts encased in a housing, I originally thought the housing was some sort of locking mechanism that you peel back and remove the individual nuts one by one.

It seems though that the whole lot comes off as a single unit - am I right?

Seems pretty flimsy for what it is considering the manual says to torque it up to 255nm, and there doesn't seem to be any independant locking device.