Compatible for Dakstra and Rooflite Roof Window No tape measure required. For the right size, find the window code reference located at the top of the open Dakstra/Rooflite roof windows. Silver thermal backing on fabric helps prevent heat / cold passing through the blind Brush seals providing a seal between the blind and siderails Blind can be opened / closed and can be positioned at any point Included: Fitting instructions, QR fitting video and 4 screws for easy instalment