Non-powered complete roof vents with galvanized bases, white screen and white garnishes replace Ventline vents. Features self-centering metal base with radius corners and interior garnish with 1-1/4" flange. Fits roofs 1-3/4" to 2-3/4". Covers all screw holes around cut-out. Positive-seal weatherstripping is leak resistant and watertight. Interchangeable with existing Ventline products. #31-1825 is a powered (12V fan) complete roof vent with all the features of non-powered vents.