PVC Opstand 160x230 cm Curb type:Straight Upstand 16 00 16 cm high for skylight 1600 x 2300 Day size = Roof opening safe connection between your roof safe connection between your roof covering and the window Roof opening = 1200 x 1500 mm is not an everyday chore Match the design to your specific project: choose a sloped version to capture the maximum amount of daylight and distribute it evenly throughout the room you choose flawless and completely watertight installation of your skylight or flat roof window