Metal Open Trim Ring for 6 Inch Ceiling R40 PAR38 Recessed Light Can - White METAL OPEN TRIM FOR 6 INCH CEILING LIGHT CAN - White Fits R40, PAR38 AND SAME SIZE COMPACT FLUORESCENT AND LED BULBS. 150W MAX INNER DIAMETER OF RING : 5-1/8 INCH OUTER DIAMETER OF RING : 8 INCH FITS IN 6" RECESSED CANS: HALO , ELCO , AND ALL SIMILAR BRANDS