Hi Andy,
Nice to hear from a "proper" window cleaner.
What rubber do you use now?
I've always used Unger soft, but lately they've lasted about 5 minutes, the quality isn't what it was.
Looking back through old posts a lot of people swear by Pulex.
I haven't tried them, but I may now....
Good job I spotted this, as no-one else bothered to reply.
They're all too busy worrying about DI's, pump pressures and resins to service their wet brushes on sticks.
Rog.