My Sierra cup dates from the 60s. The version I have is bimetal so it doesn't burn your lips. We carried it on our belts (rather than on our packs) as a kind of badge. When I was leading group trips for the Wilmington Trail Club we usually cooked in a common pot and divied up the food. The cup was perfect for that. I believe the Sierra Club did likewise and that that was the inspiration for the cup. It was also great for getting water in shallow sources, and I occasionally used it for cooking (with a foil lid). Haven't carried it in many years, but it's still something of a keepsake. Best, jcp