Galvanized Steel Roof Vent Cap 4″ with Backdraft Damper &Bird Screen for 4″ Duct
Opening: Mark and cut a 4-1/4″ hole through the roof sheathing at the desired location. Heavy-Duty 4″ Galvanized Steel Roof Vent Cap – Weatherproof Ventilation. Material Heavy-Gauge Galvanized Steel.