The recessed coupled flashing package allows 2 windows to be installed side by side with a 100mm frame gap. Recessed installations offer a more sleek, streamlined appearance, sitting 40mm deeper in the roof structure. Recessed installations also offer greater energy efficiency, and when installed with appropriate VELUX insulation collar actually offer a lower certified U-value, saving energy and providing architects with a greater design flexibility. Please note that the structural opening size required will differ depending on which flashing kit is used. Remember to consult the instruction manual supplied with the flashing prior to setting out the roof for installation.