krw wrote:
....
Along those lines... What, besides the markeering on the bottle, is
the difference between TB2 and TB3. Price, I know.

TB-III (3) passes ANSI Type-2 waterproof test; TB-II (2) only Type-I (I
know, that TB product #3 is a #2 test is cornfoozing).

The difference is the level of water resistance; neither is truly
waterproof as epoxy/resorcinal/etc. but use TB-III for exterior work
that does get wet; otherwise no real reason to use it. Well, there is
actually one other reason but not particularly related to the
water-resistance issue; TB-III has quite a lot lower chalk temperature
(I forget the exact number and am too lazy to look it up at the moment
, after all it is Labor Day vbg) but it's roughly 50F. That can be
a benefit in exterior use as well.

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