Running around the edge of the seat is some rubber edging strip, this is used to protect the cover from the otherwise sharp edge.
Once thats pulled off, it leaves the metal seat covered in foam. Now the foam isn`t the stuff you`ll find inside the cushions of your sofa, its thick density stuff which simply means it doesn`t compress as much when weight is applied to it. If you ever need to replace it or source some for a new build, then your local camping shop is the place to go cos its the same stuff they make bed roll out of. Had i made this seat, i would not have used a single thick piece, but would have built the thickness up using several layers of thinner stuff, but this isn`t a seat build thread

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