A better way? to keep RTV usable.
When the Black RTV gets hard at the cap, I take a scratch awl to the bottom of the tube where the RTV is soft.
Squeeze out what I need through the hole, then roll the tube bottom up a ways over the new hole to seal it.
Repeat with another new hole next time. Keep rolling it up from the bottom to get the most use out of your RTV purchase.
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