I had this placard lately. I am familiar with the Class 4 placards, but never seen this. Almost looks like a hybrid of 4.1 and 4.3 (dangerous when wet) . The next question is, you guys that run the PA Turnpike, is this something that is restricted?
Not unless it is the new 1..The Old one was green and stated Flammable when wet on it.
Correction it was blue and said Dangerous when wet.
Here is a link that shows DOT Hazmat Placards, but the one show above is not on the list HMMM weird.
Weird HazMat Placard 
Linear Mode
