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Sea, beer and a calculator.
(feddit.uk)
A random shot of my calculator 5000 miles from home while I enjoy a beer near the Pacific. We had been discussing how much water was on earth and what size of a ball it would make. I have no affiliation with the brewing company so apologies for the product placement.
Yes, looks like coated aluminium - not unlike a can but a little thicker and with no sharp edges. I've not seen these before but I think they are disposable/recyclable - i.e. a replacement for a plastic cup and far more pleasant to drink from. I took mine home as a souvenir, but I have had to unsquish it today taking it out of hold luggage.