I purchased the 12X12 sheet only to test to see if it would hold water - when formed into a bowl or cup. I first made the sheet into a large bowl, trying not to wrinkle it any more than necessary or cause much wear to the existing creases. Almost immediately after I filled the bowl with water, the bowl started leaking along the creases. I'd say it leaked less than the other extra-heavy aluminum foils I've tested (about half as many drops per minute).

I also noticed that the Use/Instructions (that came with the aluminum foil) states that if this aluminum foil is shaped into a bowl, you can "Use to scoop water from shallow water supplies." Nowhere in the instructions does it state that it is watertight. I would have thought that if the manufacturer thought it would hold water, they would say it would in the Use/Instructions.