The Tatonka Stainless Steel Water bottles are remarkably lighweight for a Stainless Steel bottle (@ 230 grams) being only 85 grams heavier than the equivalent Sigg Alu 1 litre Bottle. Problem with plastic and the lined Aluminum Siggs etc is that when all else fails the Stainless steel bottle can be heated over an open fire to boil water and provide warming drinks. The quality of the Tatonka Water bottle is excellent also.