Identify the part - what is it?

vtech said:

Perhaps you may not be aware but on this side of the pond the term "Super" is often used to denote "big quantity" which may not make a whole lot of sense to our friends in UK ( hey, I have British relatives)----but sorry I did not start the term

... they are really exceptionally unreliable-

I'd have to disagree with that sentence;
Granted it may be unreliable in Consumer Electronics which is mostly based on design issue and not critical. (Although countless number of them were used throughout the product cycle).
When designed properly, lifetime hours are not that far from the respective datasheets. There are many factors involved with several reports by likes of Yamaha, Panasonic ELNA and Mitsumi
Speaking of reliability, in Aviation, Airbus 380 has been using super capacitors for some time (Emergency evacuation sliders). Wonder how reliable is that

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dr pepper said:

The ones I pictured were pulled from professional it gear such as a Hp server, so I would have thought quality will be good.
I'v seen others that look like a rechargeable battery, I wonder if those are what Nige has issues with.

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