Recommended body worn accessories are only intended for use with the standard or thin battery door, not the sport clip.
While there may be differences between the SAR levels of various phones and at various positions, they all meet the government requirement for safe exposure.
The FCC has granted an Equipment Authorization for this model phone with all reported SAR levels evaluated as in compliance with the FCC RF emission guidelines. SAR information on this model phone is on file with the FCC and can be found under the Display Grant section http://www.fcc.gov/oet/fccid after searching on FCC ID
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