Overall Dimension of Plastic (includes flange) 49" x 49" Flange 1 1/2", Dome dimension 46" x 46" Thickness .118 Approximately 1/8" Height of Outer Dome 9" Height of Inner Dome 7 1/2" Material: Acrylic Only (Vertical Rise unavailable in Polycarbonate) Vertical Rise Profile or Gradual Rise Profile (Both are commonly found in Texas and Oklahoma). Gradual Rise dome will NOT work in a vertical rise skylight frame. The Vertical Rise Profile is sometimes referred to as Quick Rise (most commonly found in skylights manufactured by Solar Accessories) We make all sizes! Please contact us if you need the size to be special. This item is made to order (No Returns or Exchanges)  Please allow 3-5 days to prepare for shipping (larger quantities may increase lead time) SHIPPING - This item ships on a pallet 54" x 54" LTL Freight This product is designed for use in an existing residential/commercial framed gradual rise skylight where the frame and retainer are screwed together to hold the plastic in place.  There is no such thing as a STANDARD size or deduction between the Outside of the retainer frame and the plastic underneath.  Please remove screws and measure tip to tip of plastic prior to ordering.