These items paint Assault Rifles in 2 materials: platinum and carbon.
Platinum looks good on some dark material. I think, from all dark material carbon is best for platinum background. Classical noble metal and modern composite material - presious and high-tech at the same time.
Literally some kind of a "black and white" - bright heavy expensive metal and dark light cheap composite.
I think the idea of painting weapons at these material is deserve attention.
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If you find any mistakes, defect or just way how to make skin better, post in comment, i will fix skin.