I use Reynolds Heavy Duty. I use 1 layer. I cut it about 5" wide. I don't know about elsewhere but where I live it's only available in a long box. For a 5" wide piece by however long it is I get enough foil for 4 regular bowls or 3 small Super Chief bowls (they are wider). A box of Reynolds Heavy Duty should last a long time. I've had a box for 3 weeks now and smoke everyday (OK most times twice a day
) and there's still plenty left.