Infrared Window, Crystal Insert Size 75mm dia, Viewing Aperture Size 68mm dia, Window Thickness 2 mm, NEMA Rating 4, 12, IP Rating 67, Gasket Maximum Temperature 232 Degrees C (450 Degrees F), Body Maximum Temperature 232 Degrees C (450 Degrees F), Optic Maximum Temperature 232 Degrees C (450 Degrees F), Voltage Range Any, Components CV300, ClirVu (R) Infrared Window, Body Material Zinc/Aluminum Alloy, Includes Hand Turn Door, Manufacturers Warranty Length Limited Lifetime. This item has been restricted from sale in the following state (s): []