---
product_id: 267848373
title: "1 lb Jar, Black, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs"
brand: "flex paste"
price: "€ 57.74"
currency: EUR
in_stock: true
reviews_count: 5
category: "Flex Paste"
url: https://www.desertcart.hr/products/267848373-1-lb-jar-black-waterproof-paintable-putty-spackle-sealant-fill
store_origin: HR
region: Croatia
---

# Dries underwater Fully paintable finish Waterproof & UV resistant seal 1 lb Jar, Black, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs

**Brand:** flex paste
**Price:** € 57.74
**Availability:** ✅ In Stock

## Summary

> 🛠️ Seal it, paint it, forget it — the last putty your projects will ever need!

## Quick Answers

- **What is this?** 1 lb Jar, Black, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs by flex paste
- **How much does it cost?** € 57.74 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/267848373-1-lb-jar-black-waterproof-paintable-putty-spackle-sealant-fill)

## Best For

- flex paste enthusiasts

## Why This Product

- Trusted flex paste brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Paint It Your Way:** Once cured, paint over it seamlessly to match any décor while preventing rust and UV damage.
- • **Stay Fresh Container:** Innovative airtight jar locks in freshness to prevent waste and extend sealant life.
- • **DIY-Proven Durability:** Super thick paste fills large gaps instantly and even cures underwater for tough repairs.
- • **Ultimate Waterproof Defense:** Blocks air, water & moisture with a flexible rubberized barrier for lasting protection.
- • **Versatile Surface Compatibility:** Seals cracks and holes on drywall, concrete, EPDM, roofs, RVs, and more—indoors or outdoors.

## Overview

Flex Paste 1 lb Black is a premium waterproof, paintable putty designed to fill and seal gaps, cracks, and holes across multiple surfaces including drywall, concrete, and EPDM. Its flexible, rubberized formula blocks air, water, and UV rays, cures underwater, and comes in a stay-fresh container to maximize usability. Ideal for professional-grade indoor and outdoor repairs, it offers a durable, paintable finish that prevents rust and corrosion.

## Description

Flex Paste is an excellent waterproof sealant. It can be used on windows, doors, vents, and thresholds. It's easy-to-use and perfect for all types of indorr and outdoor repairs. It's even greawt for DIY projects. Crafts, hobbies, and so much more.

Review: fixed the problem we had
Review: Excelente producto, hace todo lo que promete. Solo lo puedes usar una vez, lo deje muy bien tapado como venía en el instructivo y se seco, pero cumple perfectamente su función.

## Features

- NEW! STAY FRESH CONTAINER – Blocks out air and locks in freshness to extend the sealing power of Flex Paste, with no waste
- COAT, SEAL & PROTECT - Penetrates deep to seal out air, water, and moisture. Once dry, it turns into a strong, flexible, watertight, rubberized barrier
- WORKS UNDERWATER - Can be applied underwater, and it even dries underwater
- FILLS LARGE AREAS - Super thick rubber paste clings to the surface and instantly fills large gaps, cracks, and holes
- FULLY PAINTABLE - Once fully cured, it can be painted any color. Helps prevent rust and corrosion, and it is UV resistant
- EXCELLENT FOR – filling cracks and holes, foundation and concrete repairs, sealing out rodents and pests, bath and shower, indoor and outdoor projects, roof, RV, motorhome, auto, marine, lawn and garden projects, DIY, hobbies, and more
- MADE IN THE USA

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B084TDS8S5 |
| Best Sellers Rank | #116,615 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) |
| Brand Name | Flex Paste |
| Color | Black |
| Compatible Material | Wood, Glass, Tile, Concrete, Aluminum, Metal, Brick, Stucco, Masonry, Copper, Fabric, Fiberglass, Ceramic, Porcelain, Natural Stones, Roofing, Pvc, Eifs, Cspe, Epdm, Hypalon Polyurethanes |
| Customer Reviews | 3.7 3.7 out of 5 stars (3,123) |
| Included Components | Household Item |
| Item Dimensions | 10.8 x 10.8 x 6.4 centimeters |
| Item Form | Paste |
| Item Type Name | Flex Paste 1 lb Jar (Black) |
| Item Weight | 1 Pounds |
| Manufacturer | Swift Response, LLC |
| Material Type | Rubber |
| Model | FLEX SEAL - PFSBLKR16 - BLACK |
| Number of Items | 1 |
| Part Number | PFSBLKR16 |
| Style Name | 1 lb Black |
| Supported Standards | ASTM C-920 |
| Surface Recommendation | Windows,Doors |
| UPC | 850010226804 |
| Unit Count | 1 Count |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Flex Paste
- **Item dimensions L x W x H:** 10.8 x 10.8 x 6.4 centimeters
- **Item weight:** 1 Pounds
- **Material:** Rubber
- **Style:** 1 lb Black

## Images

![1 lb Jar, Black, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs - Image 1](https://m.media-amazon.com/images/I/41XUoX1+-+L.jpg)

## Available Options

This product comes in different **Color** options.

## Questions & Answers

**Q: Can this be used on flexible surfaces?**
A: Depends on how flexible. It has to be able to adhere to the surface. It cures the same as rubber in a tire. There is some give.

**Q: Seal wet surface**
A: Hello there. That's an excellent question. Flex Paste can be applied to dry or wet surfaces and even underwater. It does not dissolve, creating a watertight seal. Thank you very much for reaching out to us with your question. Please write to us anytime. We're always happy to help. Flex On!

**Q: Flex seal pasta can it be used on curved surfaces?**
A: Yes it can be used on any curved and even upside down surface but if ordering on-line, if you open the can and the edges are turning hard return it ASAP because chances is it's hard on bottom as-well and you don't get your money worth

**Q: Can I use in a in ground swimming pool to repair a crack**
A: Yes, it can be applied underwater. It won’t dissolve or wash away. It even dries underwater! Flex Paste is easy to use. With a putty knife, trowel, spatula, roller, or stiff brush remove a smooth even layer of material from the top of the tub. Scooping deeply into the tub may cause air pockets which can dry FLEX PASTE.  Apply a generous amount using a smooth sweeping motion.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Review
*by F***T on 3 February 2026*

fixed the problem we had

### ⭐⭐⭐⭐⭐ Review
*by G***S on 4 November 2022*

Excelente producto, hace todo lo que promete. Solo lo puedes usar una vez, lo deje muy bien tapado como venía en el instructivo y se seco, pero cumple perfectamente su función.

### ⭐⭐⭐ Review
*by 関***雄 on 14 May 2025*

トップライトの雨漏りに、ガラス周りをこのペーストでシーリングしました。効果は高いけど購入の半分は固まりで使えない

## Frequently Bought Together

- Flex Paste, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs, Black, Half-Quart
- Flex Paste, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs, Black, Cartridge
- Flex Seal 2-Pack Black 17oz Stop Leaks Instantly, Waterproof Sealant Coating For Gutters, RV, Roof, Skylights, Windows

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.hr/products/267848373-1-lb-jar-black-waterproof-paintable-putty-spackle-sealant-fill](https://www.desertcart.hr/products/267848373-1-lb-jar-black-waterproof-paintable-putty-spackle-sealant-fill)

---

*Product available on Desertcart Croatia*
*Store origin: HR*
*Last updated: 2026-04-22*