ORDERING NOTE: The Hart & Cooley 16 series 12" round ceiling diffuser is specifically made to cover a 12" hole in the ceiling. The overall outside diameter of the grille is: 15-15/16" (with three holes for mounting)
Designed to fit a 12" hole, overall diameter is 15-15/16"
Step down diffuser rings deflect air stream 360 degrees
Bright White finish
Sold Separately: Butterfly Damper For This Diffuser (12" Hart & Cooley #12)