I have an Apple wireless keyboard where the batteries slide into a tube. The batteries corroded and I can’t get them out. The only part of the battery that can be seen is the bottom of one of them. The plastic is black and the metal has two small bumps on it about the size of a pin head.
After comparing this to all the other batteries in the house, it appears that Duracell is the only brand with a black plastic casing on the bottom end and those two little bumps. After a brief call with Duracell, they are sending me a box to ship them the keyboard and they claim they will either repair or replace it.
Impressive customer service! Rare these days. I will support Duracell.
Yesterday I got a check from them for $69 to get a new keyboard. So yes, it is very impressive.