This is a 3d model, 1:1 ratio, wearable replica helmet concept of the Red X helmet. I modeled this helmet after a piece of concept art.
This file is available for purchase on my Etsy Account.
https://www.etsy.com/listing/848751975/red-x-robin-teen-titans-helmet-3d-model?ref=shop_home_active_12
Helmet profile views
Helmet sections
Reference image used