Dangly Door/Fly Screen

We need to replace our door screen and I see the ferreterias sell it by the metre. Question: Do I buy enough to replace the existing plastic strips or does the ferreteria make them up? Ours is the usual type where the plastic strips are stapled to wood and that hangs from the top of the door. Many thanks Paul and Karen

We got one of the metal chain type ones made up at the ferreteria, just gave them the measurements.

Metal ones hang better with less gaps but I find they more easily catch on trays and things as I carry them through the screen compared to the plastic type.