Set of billfold doors
Aluminum Bill fold door set
Seriously, who needs a billfold or Bill fold as big as these doors? Unless you’re going to carry around one of those Publishers Clearing House checks rather than cash it. Do you think this is a speeling problem or a lack of reading? Thanks, Ralph, for sending this crazy ad in. Keep ‘em coming.
Welcome To Fabulous Sparkyville 
Actually, “billfold doors” is a bit of finish carpentry slang from parts of the Midwest, in reference to the high price tag for such things. Despite how cheaply made the goobers are.
The correct industry in “bi-fold” door, making reference to how the door is hinged in the vertical center of its width. Such a door is often used for closets and cupboards, as the door does not intrude out into the room as much. Downside being that they cannot clear the opeing and always take up some of that opening.
They are used singly, and in pairs. They are often louvered to further reduce their weight.
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Spark may have discovered that the door is only the beginning. You need tracks, rollers and the like to go with these doors.
Which is like opening th ebillfold at the big box store . . .
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