NEMCO Plastic Eave Vent - Exhaust. 4 inch with ring 3/4 inch connecting ring. (also available with 3 inch long tail shown here, call for availability). Predrilled mounting holes. Back draft flapper.
Features
• Polypropylene molded plastic
• Pre-drilled mounting holes
• Back draft damper
• Locking ring connection on back
• Available with ¾" connecting ring or 3" along aluminum tail