How to diffrentiate Vandersteen 3A / 3A Signature

I plan to buy this speaker second hand and the owner told me that it'is the 3A sig. How can I tell the different between 3A and 3A sig.? Is there any physical sign? The only thing I saw at the back is the signature of Vandersteen but other than that no description mentioning it as 3A sig.
Hendya, Been to Richard's site? I will give you three guesses why this speaker is called Signature... and the first two don't count! Hurry up and buy them, good times are comin'
This is a toughie. Call Vandersteen with the Serial #.
IIRC, s/n will now end with 3AS
I have 3a's I bought second hand as well. One call to Vandersteen and a check of the serial # confirmed they were 3As. Curious to know what other components,(amp,subs,CDP,etc) you are using. They are wonderful speakers..happy listening
If they are like the 2Ce Signatures (and I don't know whether they are or not), they have--surprise!--Richard Vandersteen's SIGNATURE on the binding-post plate.