Snap on M4 wood handle drivers late 30s

[snapmom]

Not much info in the cats on these, snap on lists them as hardwood handle 5-1/8 in length. The early 30s black handle drivers were about this length and fit nicely into the small 9/32 drive box. The natural finish handles started showing up in about 35-36. and are about 5-3/8 inches in length. I know of two types, could be more, both types are very hard to find. (showing in pic) 1936 square shaft with a ball stop. this is pictured in the 37 and 38 cat, but described as the shorter length. Next is a 1937 round shaft with a collar stop. This is pictured in the 38 and 39 cat with the 9/32 whitworth set, shows the driver overhanging the slot.
If you have any more info in these please post.

[agmechjake]

I have a black handled M-4 Snapon/Blue Point coded 1934, it has a socket retaining ball but no ball stop or shoulder, just a square shank.