H.264 High Profile level 4.2, CODECS attribute of the EXT-X-STREAM-INF tag

Hi Experts,

iPhone6/6s support H.264 High Profile level 4.2.

http://www.apple.com/jp/iphone-6s/specs/

http://www.apple.com/jp/iphone-6/specs/

However, there is no description about "H.264 High Profile level 4.2" in apples's formal spec sheet.

https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/StreamingMediaGuide/FrequentlyAskedQuestions/FrequentlyAskedQuestions.html

What is the value of H.264 High Profile level 4.2?

e.g. H.264 High Profile level 4.1 "avc1.640029"

Thanks,

Akira Ueda