Duct Access Door Door Height 8 in Door Shape Square Door Width 8 in Latch Type Thumbscrews Material Thickness 16 ga Maximum Temperature Rating 2 300 Degrees F Mounting Stud Length 1 in Number of Mounting Stud 4 Observation Port Material Steel Rough Opening Height 6 in Rough Opening Width 6 in Standards UL Listed Product Type Access Door For Media Type Grease