Those things are awesome. I own 8 of 'em (2 gas, 2 ethanol-free gas, 4 diesel) and 2 of the 2.5 gal sizes (50:1 gas/oil and ethanol free gas)...Got on sale through Atlantic British years ago for under $40 a can delivered, and they work well.Also got a pair of Chicom knockoffs for kerosene and wish I'd coughed up the extra bucks for the real thing.But these, once filled, I've had them fall over in my truck, sit through seasonal changes from -5 to 105 and the seals hold as good as a mason jar top. No spills, no evaporative loss I can measure.But the seals DO crack and "go bad" after a few years. Get extras.Well worth the expense.And if anyone is looking to get NATO cans at a real good price (and be authentic Wavians): http://www.roverparts.com/Parts/GJC20They are of course for legality reasons (they are sold without spouts) for POTABLE WATER USE ONLY.... but deduce their complete range of liquid holding capabilities for yourself . You can buy spouts separately on the same page.