Exterior Shower Replacement Parts Hose Easy installation makes this a great add on unit as well as a replacement for all OEM units. The hatch is durable, resists salts and chemicals and is UV protected. It is paintable with little or no preparation and will not yellow or fade. The updated design also keeps the shower hose inside the hatch rather than feeding it into the RV, which also increases the possibilities for installation. Polar white, Key Lock. cut out dimensions 6 inch height x 11 11/16 inch width. Outside dimensions 8 7/8 inch height x 13 7/8 inch width.