Security Double Doors Door Type 2 Lock Type Cylindrical Material 18-gauge steel Hand LHR Thermal Insulation U-Factor 0.41 Door Opening Height 80 in Door Opening Width 60 in Thickness 1-3/4 in Agency Compliance UL 3 Hours Fire Rating For Use With 3TGC2 3TGC4 4-7/8 in 35-1/8 in 65-3/8 in 38-3/4 in