D3661 Half Glass Steel Door Door Type 3 Lock Type Mortise Material 16-Gauge Thermal Insulation U-Factor 0.41 Door Opening Height 80 in Door Opening Width 48 in Window Height 25 in Window Width 19 in Thickness 1-3/4 in Agency Compliance UL 1 1/2 Hour Fire Rating 7-3/8 in 37-5/16 in 67-1/4 in