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

  • Based on 55 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Monday, Nov 11
Order within 1 hour and 52 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 Quart Kit; Consists of 1 pint of Part A and 1 pint of Part B and produces 1/2 cubic foot.
  • 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

Brand: Fiberglass Supply Depot Inc.


Material: Foam,Resin


Compatible Material: Vinyl


Item Form: Liquid


Color: Yellow, Black, Clear


Package Dimensions ‏ : ‎ 8.27 x 5.43 x 3.7 inches; 2.84 Pounds


Date First Available ‏ : ‎ January 14, 2021


Manufacturer ‏ : ‎ Fiberglass Supply Depot Inc.


Best Sellers Rank: #32,802 in Industrial & Scientific (See Top 100 in Industrial & Scientific) #42 in Urethane Adhesives


#42 in Urethane Adhesives:


Customer Reviews: 4.3 4.3 out of 5 stars 55 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Nov 11

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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Top Amazon Reviews


  • Good for Sunfish Flotation Support
Perfect to pour into voids making older Sunfish sailboat flotation stable and re-attached to bottom of interior hull. Follow directions and use a flat stick in a drill for proper mixing and use it right away! It expands quickly but just enough so as to not deform tbe hull.
Reviewed in the United States on July 6, 2023 by Amazon Customer Amazon Customer

  • Rear
Seal around my boat fuel tank
Reviewed in the United States on July 27, 2023 by Brett Rolle

  • Seals the damn rodents out
It solved the problem of mice entering a machine at my workplace via a hole in the wall. Sets hard like concrete and gets really sticky and hot when curing.
Reviewed in the United States on May 19, 2023 by Joe

  • Good stuff!
Follow the instructions and work quickly. The foam pours easily after mixing and expands rapidly. Worked perfectly to fill and seal a baseboard area of my pole barn. Best I can tell, the estimated volumes are accurate.
Reviewed in the United States on April 25, 2023 by WTX Geo

  • Good foam for big areas
Are used it for a small area. It works too fast for that.
Reviewed in the United States on April 28, 2023 by Smitty

  • Barely covers the area
I bought this product hopefully thinking that it would expand more than it really did disappointing results
Reviewed in the United States on July 4, 2023 by michael

  • Use gloves
The reaction gets hot, so be sure to use safety gear, the stuff worked well to create a taxidermy head form
Reviewed in the United States on January 9, 2023 by Retro

  • Didn't roam up, stayed pretty low.
Super dense which was cool I guess but I needed volume which this product did not provide. Could of did something wrong but followed instructions to the letter. Maybe this is not boat filler but maybe used as concrete filler?
Reviewed in the United States on April 11, 2023 by Aqui Nelson

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