De
I would imagine a Walmart store or some other large stores get items on pallets. (we called them skids).
They come in different sizes of width and length.
Most common is 40w x 48L. there are plenty of other sizes as company's requirements do vary but the most common is the one I listed.
I used to buy re-conditioned ones where missing boards were replaced and none of it was brand new but useable.
Truckloads of them at a time.
Sometimes there is decent slats on them. Hopefully ya git one without the pesky Yeller jackets on em. That sucks..
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