Since my cage is in the way and door bars, i can't use my door cards and it looks rough as hell without something there. What have some of you lads used in experience for making your door cards?
I seen some lads using sheets of thin stainless but it ads more weight than necessary and looks untidy alot of the time.

I seen corrugated plastic sheets like what they make temporary signs out of but theres a risk of making a hole in it or putting my foot through it

My brother got a big 8x4 sheet of carbon for his rally car from DMRR up the north but thats expensive as hell.

What other material could i use?