Review on Portable Stainless Steel Camping Mug - Collapsible Cup with Keychain, Ideal for Outdoor Travel, Demountable Design, 75ml 150ml 250ml (L) by Christian Barnes

I was looking for a collapsible stainless steel cup for use in an off-road pilot's lifejacket. I wanted stainless steel so I could boil water. I wanted a foldable because carrying a body survival kit in the pilot's seat can be tricky when you have a lot of bulky items. If you don't put it on during an emergency or forced landing, you won't be able to get it off the plane. The 10 oz mug was the perfect solution. I was concerned that boiling water in it would result in uneven heating of the collapsible rings and a loss of friction fit. I had no problem boiling water. I plan to modify it with two small holes at the very top so I can hang it over the fire with a makeshift shackle if needed.