The Only Base Layer Garments Available that Protect You from Flame, Heat, Bacteria, Overheating, and Discomfort Without Breaking the Bank!XGO developed this breakthrough product in response to US Military requirements for garments that provide Features: AcclimateF/R technology makes the fabric thermostable: will not burn away, melt or drip when exposed to heat or flash flames of short duration 80% modacrylic/ 20% flame-resistant rayon stretch fabric Anti-microbial Scen