The 24" (609 mm) and 23" - 19" (584 mm - 483 mm) reducer bracket allows rack mount equipment designed for 19" (483 mm) racks to be properly installed into 24" (609 mm) and 23" (584 mm) racks. The 24" (609 mm) and 23" - 19" (584 mm - 483 mm) reducer bracket provides EIA-D standard square holes for installing OEM rails into 24" (609 mm) and 23" (584 mm) round-holed racks. This "joggled" type bracket has a slight bend in the material that keeps whatever you are mounting flush with the server frame, unlike flat brackets which cause items to stick out slightly.