I bought this set for $8.00 at auction about six months ago not knowing it was metric until a few days ago.  Note that the box does not have any writing on it (did it ever and was paper or other somehow wiped off)?  When the biding was so low I bought it to resell.  Few days ago I looked at it to see if it had a 1/2 20 in it and found out it was metric throughout.  It is all there and I'm wondering the age.  I'm beginning to think I may have too many tools?????  No, it is no longer for sale.

Probably a paper label originally.

Nice looking set and the price was right!  That was a home run.

Jim C.

It had a paper label on the flat area of the lid.  Time line- 70's - 80's.  I had one it & sold it to a guy at work to buy a metric/standard complete  combo set in about 82 or 83.  The combo set is in a blow molded case.  It takes up a lot more drawer space

Looks like it was made by Ace Hanson for Sears.
-Don

What a score! Some guys have all the luck. 

I have the same set. Bought it from Sears back in 1974 for working on my first and only foreign car. The cover label is printed in red. Here is a photo. O' by the way the car was a 1964 Ferrari 330 GT 2+2 , Wish I still had that car. 
Joe B

Thanks for all the good input, I appreciate it!