Cobra® Snow Country® Exhaust Vent for Roof Ridge allows heat and moisture to escape and helps resist snow infiltration in harsh winter weather. It provides 18 sq. inches per linear foot (67,720 Sq. m/lm) of net free ventilating area. The unique EasyTear™ Sizing feature allows you to hand-tear product in 3" (76 mm) increments - no knives necessary and less waste.