Security Double Doors Door Type 3 Lock Type Cylindrical Material 18-gauge steel Hand LHR Thermal Insulation U-Factor 0.41 Door Opening Height 84 in Door Opening Width 96 in Thickness 1-3/4 in Agency Compliance UL 3 Hours Fire Rating For Use With 3TGF8 3TGG1 7-3/8 in 39-5/16 in 71-1/4 in 42-7/16 in