HEAVY DUTY DOOR LOUVERS FEATURE FLANGED FRAME WITH WELDED AND/OR STAKED MITERED CORNERS FOR ADDED STRENGTH. THE BLADES ARE INVERTED V STYLE SPACED ON APPROXIMATELY 5/8″ CENTERS FOR MAXIMUM PRIVACY. THE LOUVERS CAN BE USED FOR THE TRANSFER OF AIR THROUGH ANY BARRIER AND ARE IDEAL FOR USE WITH 1-3/8″ TO 2-1/4″ THICK WOOD OR METAL DOORS. COMES STANDARD WITH COLOR MATCHED #8 X Â3⁄4″ PHILLIPS HEAD MOUNTING SCREWS AND 204-R1 CLEAR ANODIZED FINISH.