Oh, and the math. 3mil is a really good trash bag for the shop(reference).
1mil = .001 inch = household trash bag
3mil = .003 inch = lawn/shop trash bag
20mil = .02 inch = debit card?
80mil = .08 inch = foil backed butyl
80mil is between 1/16" and 1/8", closer to 1/16.
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