Stamp on underside of Eames la fonda chair question  

Does anyone know what this stamp means and if the three dots in the center of the stamp are the same thing as the three raised fiberglass dots on the underside of the chair? I believe that the three raised dots are from an earlier period chair, and a thicker fiberglass, is this correct?
Also, can you give me a year as to when these may have been made?
There are also numbers under the embossed logo. Can you explain what those numbers mean as well. I have tried to find this info on the form, but couldn't see any questions related to this subject.
Thanks for your help!