Thank you for replying to my previous question. I would have to say that the 1 paint can shaped container of #0996 is at least 15 yrs old, and only about 1/4 remains, and still works. It is a red white and blue container, and it would dissolve varnish/gasket material in about 30 mins, or less. A few years later the labeling color changed to what it is now, like a yellowish color added to the labeling. And it seamed like the mixture was a little thicker, and darker colored. I have been using it, as it is available retail, local. But it seems to take hrs to do the same job as the older version. I always assumed that ongoing environmental/health issues, (like always) forced a formula change to something, more tolerable. I own a small auto repair shop, and not a scientist, per say. But time is money :) It`s still a time saver, I believe. Also, I use the B-12 aerosol cans, on particular varnishes, and the fuel treatment, is my go-to for injector maintenance. Thanks in advance, Dave