Hmm, I wonder if the plastic covers are the right type of plastic to emmit the proper temperature for a good IR reading, I haven't researched it yet, but its food for thought. Connections on wires are almost always hotter than the wire itself.
But with that said, i also trust those connectors, however i only trust them with solid wire, mainly because they are such a pain to use when connecting stranded, 14 AWG or otherwise. I really like the red connectors rated for 10 AWG, major time and wrist saver
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