Soudal Genius gun Champagne Gap filling Expanding foam 750ml.This 750ml water resistant fast curing gap filling expanding foam from the Genius range by Soudal has been specially designed for improving thermal and acoustic insulation and eliminating drafts or thermal bridges around the interior and exterior of your home. Simply apply and leave for 1½ hours for a bead of 3cm to dry. It comes in an easily storable and transportable aerosol and expands to approximately 30 times the size of the can. If you\'re using it during redecoration projects it\'s sandable and paintable making it perfect for giving a smooth professional finish once dried.