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Fiberglass Supply Depot

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

    • Based on 212 reviews
Condition: New
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$75.99 Why this price?

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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, May 15
Order within 9 minutes
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Features

  • Flotation Foam is a polyurethane 2-part foam that, when mixed in equal parts and poured in place this foam will soundproof, insulate, or provide extra buoyancy.
  • 4LB. Density polyurethane flotation Foam 1 Gallon Kit; Consists of 1/2 gallon of Part A and 1/2 gallon of Part B and produces 2 cubic feet.
  • Once fully cured this foam can be laminated over with any type of polyester, epoxy or vinyl ester resin without melting.
  • The 4LB density also works well in floating decoy or taxidermy applications as well as many other sculpting, casting, carving and other filling applications
  • All expansion rates and times given are temperature critical. Temperatures below 75 F will lower the expansion rate therefore requiring more foam. Ideal working temperature is 75 to 80 F or above. Accurate measuring of these products is extremely critical. Working time before foaming: approx. 45 seconds Time before full expansion: approx. 5 minutes

Material: Foam,Resin


Brand: Fiberglass Supply Depot


Coverage: 2 cubic feet


Recommended Uses For Product: Flotation, Soundproofing, Insulation, Filling Voids, Sculpting, Casting


Manufacturer: Fiberglass Supply Depot Inc.


Product Dimensions ‏ : ‎ 10 x 9 x 6 inches; 10.49 Pounds


Date First Available ‏ : ‎ August 19, 2021


Manufacturer ‏ : ‎ Fiberglass Supply Depot Inc.


Best Sellers Rank: #43,779 in Industrial & Scientific (See Top 100 in Industrial & Scientific) #67 in Urethane Adhesives


#67 in Urethane Adhesives:


Customer Reviews: 4.4 4.4 out of 5 stars 212 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, May 15

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Good product.
Works well. Be quick and ready for it, it expands quickly and will come for you if you're not prepared to control it.
Reviewed in the United States on March 8, 2025 by Richard Booth
    • Dense and low expansion
I am used to working with 3lb foam and wanted to try a 4lb foam for a project that needed some extra stiffness. This product didn't disappoint. The volume of foam that it made wasn't as much as a lighter density, but it set off and hardened extremely quickly. I was able to do my project quickly and get it out of the way. Thanks for making it easy. ... show more
Reviewed in the United States on September 24, 2024 by SethV
    • Really expands
Worked awesome, structual
Reviewed in the United States on November 3, 2024 by Amazon Customer
    • Great
Great
Reviewed in the United States on December 24, 2024 by Tojax
    • Is as advertised
Just follow the instructions and the product will do its job. It gives you just enough time to mix and pour to finish your project and sets up solid enough to stand on within 10 minutes. Can easily withstand the weight of a person bouncing up and down on it. Just wish that it would expand a little bit more, having to buy a few more jugs to finish my boat project. Definitely gets pricy. ... show more
Reviewed in the United States on May 2, 2023 by Trevor
    • Great customer support from manufacturer
I called late on a Friday afternoon to ask a quick question about the prep work and cleanup supplies i should have ready before i mixed it, and actually talked to a REAL person! Super helpful, down to earth, and friendly. If you are using this foam on a project for your self (outside of a commercial application), trust me that the guys who manufacture and answer the phone are just like you [us] doing the same silly weekend projects that our wife's yell at us for. Great manufacture, with excellent customer service! ... show more
Reviewed in the United States on January 12, 2024 by Amazon Customer
    • Not worth it
This product was worthless. Way too expensive, didn't foam up. For $76.00 this was a joke. Just use spray expanding foam. Way cheaper and expands more
Reviewed in the United States on February 2, 2025 by Amazon Customer
    • Awesome.
Goes off fast, be ready.
Reviewed in the United States on September 29, 2024 by portlyguy

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