What is the best support (frame) for grave blankets?

Question

My mother-in-law and her family has been making grave blankets for many years and have used several materials and styles. I'm looking for something that can be used from year to year and is easy to store. We make about 3 each year. 2 are about 10 miles apart and the third is 30 miles away. We use a pickup truck to transport them.

Answer 1

square frames if posible pentagon frames

Answer 2

Rigid wire.

Answer 3

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