Heavy-duty rust-free integral screen. 50 Square inches of Net Free Area airflow each. Galvanized steel construction. Square top design. Suitable for 3/12 to 8/12 roof pitch. Part of a balanced attic ventilation system for year-round airflow. Helps to fight heat and moisture buildup inside an attic as well as ice dams in cold climates. Requires intake ventilation for proper performance. Use the Lowe's online calculator to determine how many are needed for each attic.
