Close the gap beside or above your Lüften1, no tools needed. The kit includes 5 magnetic closed-cell foam modules (8", 4", 2", 1" and 0.5") that snap together to match the width of your opening.
Fits openings up to 25" with the kit alone
Wider window? Add one 8" module ($10) for openings up to 32⅞", or two for up to 40⅞"
Place the larger modules against the unit and the smaller ones at the end. Choose a combination slightly wider than the gap: the foam compresses about ½" for a snug fit.
