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Answer to "I want to upgrade Bluetooth Card(Airport Card)."IMHO you'd have to use the activation tool to activate Continuity. But referring to your original question I'd like to mention that my MBA 12" Mid 2011 does BT Low energy being supported. AFAIK LE is part of the BT 4.x specification and doesn't work with older versions. Thus I assume my MBA has BT 4.0 LE.