The other day I needed to replace my Bosch Aero Twin A539S wipers, after they became noise and not clearing properly. Even cleaning did not work. Even though I had a new set, I also had a pair of Bosch wiper rubbers from a set of universal Bosch wipers that didn't work as good. I discovered the version of Aero Twins fitted to the car have a little latch, so the end could be removed and slide the rubber insert out. This mean you can just buy good quality wiper rubber inserts of the correct size (