3M Polystyrene Foam Insulation 78 Spray Adhesive is a high solids, adjustable lace spray aerosol adhesive for bonding most types of insulation such as fiberglass, expanded polystyrene foam, and extruded polystyrene foam. It bonds expanded or extruded polystyrene and other insulation materials to themselves and to other surfaces without degrading the foam. The 3M Polystyrene Foam Insulation 78 Spray Adhesive is fast drying, it bonds with strength greater than foam itself, has a spray pattern width that adjusts from 1” - 5” with high coverage.