Help identifying a wrench and extension

[C1070RS]

The first one is a stout 16" long 3/4 drive extension that has 2 springed balls on the male end, only one I've seen like that; and no marks at all except for the 2 grooves on the larger dia on the female end. It's heavy and in perfect condition.

The other is an old carbon steel open end wrench with only an "S" and a symbol of a circle with something not very ledgeable within it. The tool is 6 3/4" long and the end openings are approx 11/16 and 13/16.

Thanks!

 

[C1070RS]

Extension looks to be S-K.

Is that because of the 2 grooves in the head?

 

[Oldtuleguy]

Yes the sk extensions of that time period were unmarked, but the grooves are a giveaway.

 

[r_olson_06]

Agree on the extension. I have the same one in my G/S Tiger set.

Looking for the following Plomb Pebbles Wrenches 3061, 3070,

 

[C1070RS]

Yes the sk extensions of that time period were unmarked, but the grooves are a giveaway.

What time period are we talking?

 

[Oldtuleguy]

This set is from 1940 or so, sockets are marked but all the drive tools are unmarked.