Sorry Miriam, I hope that my joke didn’t backfire on me. 710 is simply the word OIL read upside down and backwards.
I found an auction a while back on that auction site that listed a Model 710 sewing machine, and the photos of it included a shot similar to mine of the word OIL upside down. I got a big charge out of it and decided to adopt it as my “secret weapon” maintenance product for sewing machines.
I thought it was hilarious, but then, it doesn’t take much to entertain me, and sometimes I crack myself up with goofy stuff like this......
CD in Oklahoma