Duct Access Door Door Height 19 in Door Shape Rectangular Door Width 23 in Latch Type Thumbscrews Material Thickness 16 ga Maximum Temperature Rating 2 300 Degrees F Mounting Stud Length 1 in Number of Mounting Stud 16 Observation Port Material Steel Rough Opening Height 16 in Rough Opening Width 20 in Standards NFPA 96 Compliant UL Listed Product Type Access Door