This is an exhaust vent and must be used in conjunction with adequate intake vents for proper operation. Dual slant-back style, self-flashing roof mounted attic exhaust vent. Two model 770 roof louvers crimped together. Painted units are embossed for durability and extended paint life, and blended appearance with shingles. Features a bird-proof construction, louvered sides are seamed to the top and the top is riveted securely to the base flashing; three louvered sides open upward to prevent shingle discoloration; weather-tight collar, seamed to the base flashing; and large nailing flange.