Okay-- thanks to this awesome community, I discovered Sintra board, which I'll be using for the rest of the armor for my mando. Any tips?
Here's the link: I was thinking 1/8"and 12 by 24'', (2 sq ft) that should be enough?
[URL unfurl="true"]https://www.amazon.com/dp/B08NK3GD2K/ref=sspa_dk_detail_2?pd_rd_i=B08NK8WKNC&pd_rd_w=Ka2b9&content-id=amzn1.sym.eb7c1ac5-7c51-4df5-ba34-ca810f1f119a&pf_rd_p=eb7c1ac5-7c51-4df5-ba34-ca810f1f119a&pf_rd_r=25AP3TW6F4E0AT6W7DM9&pd_rd_wg=knBfh&pd_rd_r=c1dbac8e-0cce-46b0-bc64-2e6df6cc632c&s=industrial&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw&th=1[/URL]