We were searching for a long time to find this mini filter - now we find it. Over the years various deposits (lime, antifreeze residues, etc) sediment in the wiper fluid tank, which are pushed from the pump to the spray nozzles. Is the spray nozzle clogged once, it is really laborious to clean it. In contrast, this filter is the answer - it is plugged into the fountain solution hose between the wiper water pump and the spray nozzle.
This filter fits to our fountain solution hose s-pvc-4 and s-pvc-5