That's not any coating. Tested by Kevin Talbot UK and Bigsquidrc crew. Before drilling holes - check on model how it fit! The item "Original Unbreakable body V3 for Traxxas X-maxx Black" is in sale since Friday, November 16, 2018.
This item is in the category "Toys & Hobbies\Radio Control & Control Line\RC Model Vehicle Parts & Accs\Body Parts & Interior\Cars, Trucks & Motorcycles". The seller is "rcmaniacs" and is located in Obninsk. This item can be shipped worldwide.