Hi,
I am coming across these PP3 9V batteries with a plastic ring around the negative spring terminal.
Panasonic are the only ones I've see so far.
This one was in the box with a Hakko FG-100 Thermometer, that you use to check/cal your soldering iron.
Sorry for the quality of the pic, not good focus under about 100m.. :smiley
The clip terminal that it is on, does not look as though it has as much material as say Duracell or Eveready, its probably not as durable to clipping on and holding.
Marked as 6F22-9V, Industrial, Extra Heavy Duty, Not For Retail Sale.
Tom..
PS. Should also have marked, "Not for Arduino Projects".
That would be to prevent you from connecting the battery backwards. It is necessary because of the gradually declining average IQ since the batteries came into general use about 70 years ago.
Back when they were transistor radios.
My mum had a hand size 6 transistor radio, it took 2 x AA and she used to play while gardening.
It was all germanium transistors and from what I can remember it was a pretty good performer.
It came in a "leather" carry pouch.
Sold by "SINGER" the sewing machine people.
When we cleared parents house out, I found it, it needed some attention.
It now sits in a relatives radio collection/museum.
He said it needed a transistor replaced, which he did and it sprang back to life.
