What is this mark?

[coolford]

This mark appeared here or somewhere else before, but I didn't have any of the wrenches then and cannot remember who it represented.  The wrenches are all thin like tappet wrenches and are not plated.

[MAD]

From Alloy Artifacts site

http://alloy-artifacts.org/trademarks-and-logos.html

X-Circle    Duro Metal Products          Stylized "DC" denoting Duro-Chrome

[coolford]

Much thanks Mad!

[d42jeep]

The Circle DC was used on both Duro and Indestro tools during WW2 production.
-Don