I use 20 lb external tanks for my MH because of one thing - the Grill Gauge.
linky. In the link, scroll down to the "Product Description" where it talks about why tank exchange companies choose to label their tanks as 15 lb tanks. The take-away for me is I'm beginning to take my Grill Gauge and weigh the tanks after I get them refilled. Why? A few of the stations that I use for propane write the info on a slip of paper that I take to the cashier to pay for the gas. There is a potential for dishonesty buy the merchant. When I am able to I also make a point to watch the gas meter says after the attendant finishes filling the tanks (or the MH's propane tank). I want to make sure that I get what I'm paying for.
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