looks like a US plug tucked away there at the side...why do we need an extra usa adapter for $1 usd then?
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its a good question. I actually beleive that you do not need the adapter. look at it:
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It looks like it adds a grounding pin, but otherwise serves no purpose (that grounding effect wont transfer to the R1 AFAIK)
Is it just me?
That plug does not look like it fits that adaptor.
it will probably fit: see those two vertical slits in the bottom row.
however, i suggest to order without, then just go to target, best buy, home depot, etc. to get one.