Difference between CaiKleen 41 & CaiKleen NF

I have some confusion concerning the degreasing and cleaning solvents. What is the difference between CaiKleen 41 and CaiKleen NF.
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The former CaiKleen 41 was an excellent flushing and degreasing solvent rather than a true contact cleaner. It could, however, be aggressive to some plastics because it contained HCFC 141b. It is no longer available, per EPA regulations.

The CaiKleen NF, on the other hand, accomplishes the same result, and is non-flammable, evaporates quickly and is non-aggressive to most plastics.