Originally Posted by
Salubrious
If a 1936 then it is a type K hub which have much prettier graphics than the later hubs. So right by where it says 'K' you will find a number; '6' will be 1936 (seems to me the AW was introduced in 1938).
I went to the S-A heritage site to check on that since I speculated 1936:
Sturmey-Archer Heritage :: History
Looks like there was some overlap between the K hub and the AW. Actually, I think I have a K hub in the bin that's a 1937.