Black plastic base, attached hose flange. 3" duct.
•Material: Chrome-plated zamak, plastic
•Dimensions: 2-1/4"H x 5-5/16"W x 6"L
•Cutout Size: 3"
The screw hole for this vent cover goes THROUGH the front to the back of vent cover. Does not screw down into it like PERKO.