Skylight Inner Dome for a 22” x 14” Skylight opening. An Inner Dome provides a layer of insulation and reduces condensation forming on the outer skylight. Molded of white ABS plastic material with a clear center insert. Complete your replacement with a new outer dome, SL1422. When paired with an ICON SL1422 outer skylight dome: the 2" depth is appropriate for a minimum 1-1/4" roof thickness, the 5" depth is appropriate for a minimum 4" roof thickness. Fits all standard 22” x 14” skylight openings.