He said he has a 50-Amp motorhome.
This adaptor sends up to 30 Amps on one leg, and up to 20 Amps on the second leg. Since the RV and cord are rated for up to 50 Amps PER leg, it should work fine for him.
Like others stated, it doesn’t apply to 30-Amp rigs (like OP) because they only have one leg.
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