Universal bracket for mounting 4” & 6” AC Opal to 3” or 4” junction boxes. Universal bracket is included with NLOPAC-R4509 series. Compatible Luminaires: NLOPAC-R4T24: 4? Title 24 AC Opal NLOPAC-R4509: 4? AC Opal NLOPAC-R6T24: 6? Title 24 AC Opal NLOPAC-R6509: 6? AC Opal