What Type of Plastic are Door Armrest Bases?

What car
what year
what trim level

Repos or OEM!

Most likely the plastic on repos is different that the OEM pieces.
OE, '70 Valiant specifically, don't believe trim level matters on those. I'd read "opinions" of ABS etc., & the parts strike Me as styrene, but there were enough types possible that I want a "know" answer. I know the grilles in that era are styrene....but being molded in so many colors & a somewhat stressed component, I wasn't sure what Mopar chose to mold them out of.