· This is the interior dome, sometimes called the inner garnish, for the skylight.· For a 14 x 22 clear exterior dome use item #777104692.· Skylight is used with a ceiling thickness of 3"· Outer Dimensions: 23 7/8" x 16" x 4 5/8"· Inner Dimensions: 22" x 14"· Skylight is used with a ceiling thickness of 3"