---
product_id: 214989981
title: "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"
brand: "flex paste"
price: "HK$203"
currency: HKD
in_stock: false
reviews_count: 8
url: https://www.desertcart.hk/products/214989981-flex-paste-waterproof-paintable-putty-spackle-sealant-fill-gaps-cracks
store_origin: HK
region: Hong Kong
---

# Fully paintable & UV resistant Waterproof & dries underwater 9 oz thick rubberized paste 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

**Brand:** flex paste
**Price:** HK$203
**Availability:** ❌ Out of Stock

## Summary

> 💪 Seal it, paint it, forget it — Flex Paste has your repairs covered!

## Quick Answers

- **What is this?** 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 by flex paste
- **How much does it cost?** HK$203 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.hk](https://www.desertcart.hk/products/214989981-flex-paste-waterproof-paintable-putty-spackle-sealant-fill-gaps-cracks)

## 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, watertight barrier that blocks air, water, and moisture for lasting protection.
- • **Paint It Your Way:** Once cured, paint over it seamlessly to match any surface and prevent rust or UV damage.
- • **Freshness Locked In:** Innovative airtight container keeps the paste fresh and ready, eliminating waste and extending shelf life.
- • **Super Thick Coverage:** Clings instantly to fill large gaps, cracks, and holes on diverse materials from drywall to concrete and EPDM.
- • **Underwater Application:** Unique formula allows application and curing even underwater—perfect for emergency fixes.

## Overview

Flex Paste is a premium 9 oz black rubberized putty designed for professional-grade sealing and patching. Waterproof and UV resistant, it forms a flexible, watertight barrier that works even underwater. Its airtight container preserves freshness, while its thick consistency fills large cracks and holes across multiple surfaces. Fully paintable and corrosion-resistant, it’s the go-to solution for durable, seamless repairs on walls, roofs, RVs, and more.

## 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, Cartridge - desertcart.com

Review: Good stuff, simple to use - I was worried bjt, it worked I repaired a fiberglass bathtub, it was thick, I globed it on and to worked good, my can was air tight and fresh, not permanent but long lasting patch, don't get it on your clothes,,,
Review: Perfect water sealant with no leaks on cracked items - I had an outdoor water fountain that I forgot had water in it and it froze.... Which made the whole fixture crack at the water expanded. I use this flex paint to see if it would be able to seal the cracks and hold the water and it did!!! No more leaks and i the adhesion holds really really well. Drives fairly quickly like maybe 24 hours. The smell is a little strong so I would let it sit outside as it dries.

## 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

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B084TDD2FB |
| Best Sellers Rank | #18,515 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #56 in Hardware Sealers |
| Brand | Flex Paste |
| Brand Name | Flex Paste |
| Color | Black |
| Compatible Material | Wood, Glass, Tile, Concrete, Aluminum, Metal, Stucco, Masonry, Copper, Fabric, Fiberglass, Ceramic, Porcelain, Natural Stones, Roofing, Pvc, Eifs, Cspe, Epdm, Hypalon Polyurethanes |
| Customer Reviews | 3.9 out of 5 stars 5,981 Reviews |
| Included Components | Household Item |
| Item Dimensions | 11.25 x 3 x 3 inches |
| Item Form | Paste |
| Item Type Name | Flex Paste 9 Oz. Cartridge - Black |
| Item Weight | 9 Ounces |
| Item dimensions L x W x H | 11.25 x 3 x 3 inches |
| Manufacturer | Swift Response, LLC |
| Material | Rubber |
| Material Type | Rubber |
| Style | 9 oz Black |
| Style Name | 9 oz Black |
| Surface Recommendation | Windows,Doors |
| UPC | 850010226859 |
| Unit Count | 1.0 Count |
| Warranty Description | 1 Year Limited |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Flex Paste
- **Item Weight:** 9 Ounces
- **Item dimensions L x W x H:** 11.25 x 3 x 3 inches
- **Material:** Rubber
- **Style:** 9 oz Black

## Images

![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 - Image 1](https://m.media-amazon.com/images/I/61cv+cPofgL.jpg)

## Available Options

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

## Questions & Answers

**Q: Can I use it around the base of my toilet?**
A: You can! We recommend keeping it near the base of the toilet and not spreading it through the floor as it can become slippery when wet. Let us know how the project goes!

**Q: can flex glue be used to repair a roho inflatable neoprene wheelchair cushion?**
A: not sure, they make a tape like duct tape, that might work.  The paste is  more for sealing cracks.

**Q: can you paint after this is applied?**
A: Spray paint might eat the rubber away or anything else that has more of a solvent when you paint I wouldn’t use on this

**Q: Will it fix a hole puncture on a 8” subwoofer?**
A: Yes read my post about the puncture on my 2016 ford interceptor rear quarter panel worked like a champ on this damage from a corner of a shelf on the wall

## Customer Reviews

### ⭐⭐⭐⭐⭐ Good stuff, simple to use
*by L***K on April 18, 2025*

I was worried bjt, it worked I repaired a fiberglass bathtub, it was thick, I globed it on and to worked good, my can was air tight and fresh, not permanent but long lasting patch, don't get it on your clothes,,,

### ⭐⭐⭐⭐⭐ Perfect water sealant with no leaks on cracked items
*by F***S on December 13, 2025*

I had an outdoor water fountain that I forgot had water in it and it froze.... Which made the whole fixture crack at the water expanded. I use this flex paint to see if it would be able to seal the cracks and hold the water and it did!!! No more leaks and i the adhesion holds really really well. Drives fairly quickly like maybe 24 hours. The smell is a little strong so I would let it sit outside as it dries.

### ⭐ Does NOT work as advertised!!!
*by C***S on October 28, 2024*

UPDATE - I have been monitoring the pipe for the last few days. While I initially thought the paste was going to provide the fix I needed, that "thought" would be incorrect. The water started leaking again. Be smart/save your money and do not buy this stuff. I'm going back to what I should have done to start with - turn off the water and replace the pipe. This Flex Paste is JUNK!!!! Had a very small leak at the base of this water faucet (small droplets of water on the PVC surface). Based on the advertisement I thought the paste would be the perfect fix. I followed the directions as stated on the container. After apply a good initial coat, I still had the small leak. The next day, I applied another coat - still had the leak. The next day, after turning off the water to everything, I applied another coat heavy/massive amount of paste using both a putty knife and my hand. Left the water off for 1 to 2 hours and the leak appears to have stopped (after using most of the paste). What a pain!!! While using the paste, I was diligent in keeping the lid on the paste. At the end of each day, I would use a rubber mallet to hammer the lid on. Regardless of the tight seal, the paste still hardened. Probably would have been easier to just replace the bad piece of PVC that was leaking.

## 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, Cartridge
- Flex Seal 2-Pack Black 17oz Stop Leaks Instantly, Waterproof Sealant Coating For Gutters, RV, Roof, Skylights, Windows
- 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

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*Product available on Desertcart Hong Kong*
*Store origin: HK*
*Last updated: 2026-02-26*