[Fabric]: 6oz FR treated cotton knitted with aramid flame retardant thread. A small sample of the fabric is included in the package for customers simple trial. [Certifications]: Comply with UL requirements. ATPV12 Cal/cm² and CAT 2 Arc Rated Garment. [Safety Protection]: Our frc shirts provide the necessary protection against flash fire, short duration thermal and a CAT II protection against electrical arc flash. [Industry Application]: This fire resistant shirt is widely used in the industrial and construction work. It is designed for welders, electricians, blacksmiths, oil workers and assemblers, etc. 【Tips❗❗❗ Flame retardant shirts ≠ fireproof clothing】: Our flame retardant shirts are different in nature from fireproof clothing. Flame retardant clothing is added to the surface of the clothing flame retardant or the use of flame retardant fibers (such as aramid), when in contact with fire will slow down the burning speed or self-extinguishing from the fire, but can not completely prevent combustion, will still be charred, suitable for short-term sparks splash occasions. SKSAFETY FR Shirts for Men Long Sleeve, Welding Shirt Men's 6oz Lightweight Fire Resistant Flame Retardant Shirt CAT2 (Gray 6XL)