mnredfox, mersk862, slipbeer, MichaelKade, Captbob52, readywhenyouare,
THANK YOU all for your comments and suggestions and clarifications on the prong size. I've really enjoyed and appreciated FT over the last 14 years, and you are six of the reasons why.
I have a couple of the two-prong 3.5mm (yes, that's the size in case anyone's interested!

) adaptors, however if I have a problem with any of them, I'll ask the f/as to see if they can help. My last 777 biz flight on DL was 2011, and all I remembered was that it was two-pronged; some airlines/aircraft (e.g., BA first) have the two different-sized prongs, so I was confused on that.