From what I can figure out, the 6133 is not the US version of the 6133; the 6126 is. Basically, the 6126 is the same thing as the 6131, minus the FM radio. The 6133, however, looks lightly differently and is tri-band, not quad-band like the other two. There might be other differences, too.
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From what I can figure out, the 6133 is not the US version of the 6133; the 6126 is. Basically, the 6126 is the same thing as the 6131, minus the FM radio. The 6133, however, looks lightly differently and is tri-band, not quad-band like the other two. There might be other differences, too.