Just seen the ionics thread showing the spray nozzle they use for conservatory cleaning. Been using something similar myself for a few years and made it from the parts of an old Gardiner brush I had in the garage.
All you need is the quick release socket, the Fan jets out of the brush and the T Connector. You have to widen the screw holes slightly to take the fan jets. I just drilled them with a similar sized bit to the fan jets.cant remember the size exactly but it’s a 5 minute job to make:
Clips straight on the pole and great for rinsing off Fascias/conservatories etc.