If you are soldering connections and want to protect the joints , these mini brush caps are a good size.
Too expensive to buy them for that purpose, but if you have them anyway.
Used RTV on an outdoor electric fence, and indoor LED project.
Don't use regular RTV: it contains acetic acid which will corrode the conductors. They make an "electronic grade" of RTV.
Also, don't apply power before the RTV is fully cured, since it may explode (don't ask me how I know).
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