I got one very like this only yesterday (in a box of 65 wrenches and 50 or so sockets and extensions). Mine, though, has a slightly elongated diamond with the initials S. R. Outside the diamond are the struck letters E. I. &. C. S.
On the other side, inside the diamond, are the faint--and smaller--letters _ _ CK/R?ILL.
Mine measures 6 1/4" from sharp jaw to sharp jaw.
Any thoughts?