"MacBook Air EFI Firmware Update 2.9.1 (4.3MB)
This update replaces EFI Firmware Update 2.9 and is recommended for MacBook Air (Mid 2011) models. This update addresses an issue where systems may take longer to wake from sleep than expected and fixes a rare issue that may cause fans to run at full speed after waking from sleep.
OS X 10.9.2 and later
MBA41.0077.B11" (typo, is version after update)
Per an apple doc (later retracted), MBA41.0077.B11 was the EFI version after installing the (pulled) v2.9 update. (The EFI 2.9 update requirements noted having EFI 0077.B00, .B08, .B0E or .B0F.)
Check the MacBook Air forum for feedback. (An early report from a 13" 2011 MacBook Air owner said he updated OK. Boot rom MBA41.0077.B11 after EFI 2.9.1 update.)
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