6 Lb. Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (1 Gallon Kit)

Works great for my taxidermy molds Expands roughly 4 times liquid amount and is rock solid ( 6lb )

Used this to insulate around a bathtub and it worked great. The foam expanded exactly as expected and provided a solid, supportive fill without over-expanding or creating pressure issues. Once cured, it formed a dense, durable barrier that helps with both insulation and soundproofing. Just be sure to follow the mixing directions carefully and prep your area—it sets fast. Highly recommend for home projects where a strong, stable fill is needed

Replaced foam under floorboards in my boat and this product worked extremely well.

Works extremely well!

Measure equal parts into 2 containers. Pour into a 3rd container and stir for 20 seconds then pour into what you want filled. I used this in an aluminum sectional flag pole to make it rigid for use as an antenna mast. Worth noting, when this starts expanding it does it FAST if it’s hot outside. 1 1/2 fluid oz. of each part (3 oz. total) expanded to fill 13 inches of a 2 inch hollow pole and this stuff is hard as concrete but super lightweight. Wear gloves as you don’t want to get any on you and it does heat up when expanding and curing. It only takes 5 minutes or less for full expansion. Expands probably 10x the volume when mixed properly. This is great stuff.