Additional extension curb for installing RoofLITE+ FRE and FRF flat roof windows.

If your project to install a RoofLITE+ FRE or FRF window in a flat roof requires the use of an extension, you should use the optional FRC extension curb. This additional extension curb raises the window by 15 cm. Up to 3 FRCs can be used when installing one window.

Use of an FRC extension curb requires prior use of an additional extension curb with a flange, designated FRC F, which additionally increases the installation height by 16 cm.