TOP FITS THE TIP domestic waterworks HWW 4500 INOX ;-))

because there is no air to inflate the domestic water supply was impossible, it read only the presumption that after 10years that is Diaphragm broken :(.
Well, quickly peeped times on Amazon and also found. OK, now do not know 100% that fits this, but the price was not so high so now :).

positive:

+ Has fitted the 4500 TIP HWW-INOX
+ Low
+ Easy to install
+ Fast delivery

negative:

- No guidance (but not really necessary)
- Rubber compound = origin = suitable for potable water = not with me (it use only by rainwater)

Conclusion:

Cheap and recommendable HWW 20-24L membrane for garden use ;-).

Tip for change:

- Unplug
- Connections pump / suction / discharge line to solve (was not necessary for me, because flexible)
- Only pump from the container solve (two screws)
- Flange position with a Edding dash mark (then adjust the star holes again)
- The container is full of water, so out with it and empty or ......
- .... Outside the flange and remove membrane
- New membrane on the flange with your fingers circular emphasize long / press (so that little wrinkle disappears)
- In reverse order everything again put ;-))) together

that's it ...