Infrared Window, Maximum Operating Temperature Degrees F 450 Degrees F, Minimum Operating Temperature Degrees F -40 Degrees F, Optic Maximum Temperature 450 Degrees F, Viewing Aperture Area 5.62 sq in, Viewing Aperture Diameter 2.68 in, Viewing Aperture Height Not Applicable, Viewing Aperture Width Not Applicable, Window Thickness 0.08 in, Body Maximum Temperature 450 Degrees F, Includes 2 in IR Window, Hand Turn Door Latch, IP Rating IP67, Gasket Maximum Temperature 450 Degrees F