I have 3 assorted clamps for your collection. All are a bit rusty. They do still work though. All from the mid 1950’s-60’s.
I have a red clamp (original factory red paint) marked CIN TOOL CO (cincinati) on one side and the letter “H” (for the designer John Hargrave) and No. 555. listed on the other. This measures 3 1/2″ from top of clamp to bottom. Out of the 3 clamps, this one is the less rustiest.
The second clamp is also marked CIN TOOL CO on one side and the letter “H” 2in No 548x. This measures 3 1/4″ from top clamp to bottom.
The third clamp is marked STEEL SCREW 5 on one side and RACINE m & W.I. CO. This measures 9″ from top of clamp to the bottom.