---
product_id: 368440065
title: "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"
brand: "flex paste"
price: "R1631"
currency: ZAR
in_stock: true
reviews_count: 5
category: "Flex Paste"
url: https://www.desertcart.co.za/products/368440065-waterproof-paintable-putty-spackle-sealant-fill-gaps-cracks-holes-block
store_origin: ZA
region: South Africa
---

# Dries underwater, no compromise Fully paintable after curing Waterproof & UV resistant seal 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

**Brand:** flex paste
**Price:** R1631
**Availability:** ✅ In Stock

## Summary

> 🛠️ Seal it, paint it, forget it — Flex Paste has your back!

## Quick Answers

- **What is this?** 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 by flex paste
- **How much does it cost?** R1631 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/368440065-waterproof-paintable-putty-spackle-sealant-fill-gaps-cracks-holes-block)

## 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

- • **Seal Like a Pro:** Creates a flexible, rubberized barrier that blocks air, water, and moisture for lasting protection.
- • **Stay Fresh Tech:** Innovative airtight container locks in freshness, ensuring zero waste and maximum sealing power every time.
- • **Paint It Your Way:** Once cured, seamlessly paint over to match any surface, preventing rust, corrosion, and UV damage.
- • **Versatile Fix-All:** Ideal for walls, roofs, RVs, concrete, and more—fills large gaps, cracks, and holes with super-thick, durable paste.
- • **Underwater Application:** Unique formula allows application and curing even underwater—perfect for emergency fixes and tough spots.

## Overview

Flex Paste is a super-thick, waterproof, paintable rubberized putty designed to fill and seal gaps, cracks, and holes across multiple surfaces including drywall, concrete, and EPDM. It features a stay-fresh container to prevent waste, dries even underwater, and offers UV resistance for long-lasting durability. Perfect for indoor and outdoor repairs on walls, roofs, RVs, and more, this American-made sealant combines professional-grade performance with DIY ease.

## Description

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 | Super-Thick Waterproof, Paintable Rubberized Putty, Bonds to Wood, Concrete, Epdm, Metal, Skins 15-30 Minute : desertcart.in: Industrial & Scientific

Review: loved it - fixed the problem we had
Review: Excelente !! - 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 | #38,695 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #159 in Hardware Sealers |
| Brand | Flex Paste |
| Brand Name | Flex Paste |
| Colour | Black |
| Compatible Material | Diy |
| Customer Reviews | 3.8 out of 5 stars 3,160 Reviews |
| 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 | 454 g |
| Item dimensions L x W x H | 10.8 x 10.8 x 6.4 Centimeters |
| Manufacturer | Swift Response, LLC |
| Manufacturer Part Number | PFSBLKR16 |
| Material | Resin |
| Material Type | Resin |
| Model | FLEX SEAL - PFSBLKR16 - BLACK |
| Number of Items | 1 |
| Style | Compact |
| Style Name | Compact |
| Supported Standards | ASTM C-920 |
| Surface Recommendation | Windows,Doors |
| UPC | 850010226804 |
| Unit Count | 473.18 Milliliters |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Flex Paste
- **Item Weight:** 1 Pounds
- **Item dimensions L x W x H:** 10.8 x 10.8 x 6.4 Centimeters
- **Material:** Resin
- **Style:** Compact

## Images

![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 - Image 1](https://m.media-amazon.com/images/I/71Avii-yA1L.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

### ⭐⭐⭐⭐⭐ loved it
*by F***T on 3 February 2026*

fixed the problem we had

### ⭐⭐⭐⭐⭐ Excelente !!
*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.

### ⭐⭐⭐ 半分は固まり
*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

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**Shop now:** [https://www.desertcart.co.za/products/368440065-waterproof-paintable-putty-spackle-sealant-fill-gaps-cracks-holes-block](https://www.desertcart.co.za/products/368440065-waterproof-paintable-putty-spackle-sealant-fill-gaps-cracks-holes-block)

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*Product available on Desertcart South Africa*
*Store origin: ZA*
*Last updated: 2026-08-25*