Cobra Snow Country Advanced Rigid Exhaust Vent Premium quality rigid-style vent. Snow Guard filter helps resist snow infiltration. Includes 3 ring shank nails for easy installation. No end caps needed. Cobra Snow Country Advanced removes excess heat, prevents roof rot, and promotes energy efficiency. Provides 18 square inches per lineal foot of net free ventilating area. EasyTear feature allows you to hand tear product in 3 increments. No knives necessary and less waste. Extra-flexible hinge design allows installation on 3/12 to 16/12 sloped roofs. Width is 13.7 overall, and 11.5 for the top panel. One box contains 10, 4' lengths. Size 13.7 In. x 4 Ft., Thickness 7/8 In., Type Plastic, Color Black, Net Free Area 18 Sq. In. per Linear Ft., Roof Pitch Size 3/12 to 16/12 Roof Pitch, Pkg Qty 10, Package Type Box