SPECIFICATIONS GABLE LOUVER GLPG1412G-1/8 28 Gauge Galvanized Steel · N.F.V.: 65 sq. in. • 1/8 in. Screen • Rough Opening: 14 ¼ in. x 12 ¼ in. 14 in. 35.56 cm 12 in. 30.48 cm 7⁄8" 7/8 in.