thanks for posting
those pdfs, Gordy. As a long term user of SC2000, I've been curious about its replacement by SC4000, but none of the "end of the supply chain" vendors seemed to know anything about the change.
I had supposed it was due to toxicity issues, but seems that ozone depletion was the driving force. I guess I am happy to learn that there were no hidden hazards of great note, since I'd never used respiratory protection while patching old dinghies on the beach!