---
product_id: 280506222
title: "Frost King B2 Mortite Fingertip Caulking Cord, 1/8\" x 90 ft, Grey"
brand: "frost king"
price: "$46.62"
currency: USD
in_stock: true
reviews_count: 5
category: "Frost King"
url: https://www.desertcart.us/products/280506222-frost-king-b2-mortite-fingertip-caulking-cord-1-8-x
store_origin: US
region: United States of America
---

# Waterproof, weatherproof flexible seal 90 ft length for extensive sealing Finger-press application, no tools needed Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey

**Brand:** frost king
**Price:** $46.62
**Availability:** ✅ In Stock

## Summary

> 🛠️ Seal Smart, Live Cozy — The Ultimate Draft Defender

## Quick Answers

- **What is this?** Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey by frost king
- **How much does it cost?** $46.62 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/280506222-frost-king-b2-mortite-fingertip-caulking-cord-1-8-x)

## Best For

- frost king enthusiasts

## Why This Product

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

## Key Features

- • **All-Weather Performance:** Creates a durable, weatherproof barrier that blocks drafts and moisture, even in fluctuating temperatures.
- • **Flexible & Removable Seal:** Won't harden over time, maintaining a tight seal while allowing easy removal or repositioning.
- • **Multi-Strand Customization:** Tear off 1 to 5 strands to fit any gap size, ensuring a perfect, tailored seal every time.
- • **Versatile Surface Compatibility:** Seals wood, metal, glass, masonry, plastic, and concrete—perfect for indoor and outdoor use.
- • **Effortless Finger-Press Application:** No caulking gun required—just press and seal with your fingertips for a mess-free, quick fix.

## Overview

Frost King B2 Mortite Caulking Cord is a 90-foot, gray rubber strip designed for easy fingertip application to seal gaps on porous and non-porous surfaces. It forms a waterproof, weatherproof barrier that remains flexible without hardening, suitable for indoor and outdoor use on wood, metal, glass, masonry, and plastic. Its multi-strand design allows customizable width, making it ideal for blocking drafts and moisture efficiently without the need for tools.

## Description

Frost King Mortite Gray Caulk Caulking Cord For Window 90 ft. L x 1/4 in.

Review: Good sealing, very helpful in difficult conditions but a little be temperature sensitive - Good sealing, very helpful in difficult conditions but a little be temperature sensitive so when I tried to apply it during a wind storm, cloudy, sunless day at 47º F, it was stiff and stuck to my fingers more than it stuck to the window frame. I still recommend it really did stop the significant cold air leaks (and small leaks as well) which is exactly what we wanted, When the temperature is a little bit warmer its easy to apply but when the metal window frame got down to 47º F in high winds, it got still and did not stick to the metal frame so much, I could still push it into place into the grooves that were laking a huge amount of air. NOTE: Even a tiny hole can leak a massive amount of air, so its best to use more and push it into every possible crevice to trite catch all the possible leaks. When the window temperature is cld and the caulk doesn't want to stick to the cold metal frame, it will tend to stick to your fingers so push in to the slot/crevice then slide or twist your finger to release the caulk (don't worry it washes easily off you're fingers so push it as hard as necessary to get it to stick to the frame). You will notice that once you install it that when it's cold it will harden, don't worry, it still seals the window and keeps the drafts out. When the temperature rises then it will soften again and if you need to you can then work it into the gap/crevice some more. Although its listed as 45 feet which sounds like a lot, keep in mind that it comes in 5 rows, you can tear off 1, 2, 3, 4 or 5 strands and install them, so very often you will use more than 1 strand (I often used 3 or 4 strands) so I was only able to seal one and a half standard sided windows (which is all I added to do anyway), at its low price its certainly worth buying more if you need it, use plenty so it seals your windows properly. I would give it a 5 start rating other than a slight challenge with installing it at cold temperatures (which it still got installed, it just took more effort, that was worth it).
Review: If you need it, it’s a good, easy-to-use product - I had floor-to-ceiling gaps on both sides of my stone fireplace where it met my wood-paneled walls. The gaps ranged from 1/16” to 1/4” wide. The gaps never bothered me until I saw a roach exit the gap on one side of the fireplace, zip across the stone, and then disappear into the gap on the other side. Yuck, can’t have that. A few knowledgeable people advised me to apply a clear silicone bead, but I was reluctant because I figured I’d mess it up somehow and then I’d be upset that it didn’t look good. It was sheer serendipity that I came across this product while wasting time on desertcart. The product is 90’ in length made of 8 strips across that can easily be pulled apart. In my case, I peeled off a 3 strip section (which is approximately 1/2” wide (depending on how you squish it) and, starting at the ceiling, worked my way down, using my fingers to push the product along the gap and over and around the stone (the gap is very bumpy and uneven). The biggest issue I had was holding the big roll as I rolled it down the wall. In the end, I was very happy with the seal, the overall look, how easy it was to do, how unmessy it was to work with, and the brown color that complements the paneling. I attached a photo of what it looks like up close. It actually looks much better in person because the caulk lies in recessed corners on both sides of the fireplace; it just looks like dark corners without all the detail of the up-close photo. - Easy to remove? Yes, in the beginning and for at least 1 year (in my experience). I don’t know how easy it is to remove when it dries out over time. - How long will it last? I don’t know. So far, it’s been 1 year and it’s still adhering and still looking good. - Will it damage the wood paneling? I don’t know. I guess I’ll find out whenever it deteriorates enough that I have to remove it. - Will it leave residue on the stone? See answer above. I’m thinking I should probably remove it before it hardens and re-bead the gap with fresh product. For the price, ease of use, and color, it was a good solution for my problem. I think it probably looks better than the silicone would have, too. ___________________________ Update: December 2024 (6 years after putting up the product): A small portion (about 2 ft starting at the ceiling) of the caulk fell off, but the rest is still holding fairly well. I can tell it's dry in places because there's slight movement in places down the bead. So, I replaced the bead on once side of the fireplace and will eventually get around to doing the other. Thus, it held up for a solid 6 yrs. I don't know if that's good or bad, but it seems decent to me. The caulk did not damage my wood paneling, did not damage the stone of the fireplace, did not leave any residue anywhere, and was easy to remove.

## Features

- Indoor outdoor mortite
- For use with wood, plastic, metal, mansonry, glass and concrete
- Forms weatherproof seal on porous and non-porous surfaces
- No caulking gun needed... just press in place with your fingertips
- Won't harden... so it selas tight, yet can be easily removed

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B000LNODSQ |
| Brand | Frost King |
| Brand Name | Frost King |
| Color | Gray |
| Colour | Gray |
| Customer Reviews | 4.2 out of 5 stars 6,137 Reviews |
| Full Cure Time | 24 Hours |
| Full cure time | 24 Hours |
| Global Trade Identification Number | 00038092810924 |
| Included Components | Thermwell Mortite Weatherstrip And Caulking Cord Gray |
| Item Form | Strip |
| Item Type Name | Frost King B2 Mortite Caulking Cord 19-ounce 90-Foot Long, Grey |
| Item Weight | 19 Ounces |
| Item form | Strip |
| Item weight | 19 Ounces |
| Liquid Volume | 54 Centiliters |
| Liquid volume | 54 Centiliters |
| Manufacturer | THERMWELL PRODUCTS CO INC |
| Material Type | Rubber |
| Model | B2 |
| Number of Items | 1 |
| Number of Packs | 1 |
| Part Number | B2 |
| Surface Recommendation | Window |
| UPC | 038092810924 |
| Unit Count | 1 Count |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Frost King
- **Color:** Gray
- **Full Cure Time:** 24 hours
- **Item Weight:** 1.2 pounds
- **Liquid Volume:** 54 centiliters

## Images

![Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey - Image 1](https://m.media-amazon.com/images/I/81+X3ZmpBKL.jpg)
![Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey - Image 2](https://m.media-amazon.com/images/I/61ziQmoarUL.jpg)
![Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey - Image 3](https://m.media-amazon.com/images/I/81m6EAgVdIL.jpg)
![Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey - Image 4](https://m.media-amazon.com/images/I/713-X2xBUEL.jpg)
![Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey - Image 5](https://m.media-amazon.com/images/I/71zFsQa5V2L.jpg)

## Available Options

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

## Questions & Answers

**Q: Is it easy to remove when the weather warms up?**
A: This is the reason I love this stuff!  You can apply it in the winter and pull it off in the spring.  It is so cheap, but I have also saved thicker strips for re-use by storing in a baggy and then using them in the out of the way places like a cellar window where I am not so concerned about the look of it being patched together.  You can't beat this stuff for the price!

**Q: Can this be applied outside in cold temps (20F or below)?**
A: Yes, you can apply it if the temperatures are 20F or below.   Please note that you need to divide the sections so that you have only the width that you need.   Then you need to push it INTO THE SPACE OR INTO THE CRACK for it to stay in place.

**Q: 5.5 x 5.8 x 1.2 inches? These dimentions don't even come close to the photo or a 45 foot roll. anybody have a clue?**
A: Roll has 8 single strings of caulk which are rolled over and over again but are attached like licorice strings. It’s a lot and I have a 90 ft roll. The strings are a little thin an 1/8 of an inch in diameter x 90 ft long but they work.

**Q: I have sliding windows, and patio door.  Will the grey work good to seal the drafts on them?**
A: Absolutely!  I wasn't sure how good it was going to be so I ended up ordering more. I bought the wood - colored one as well to put on places where wood meets the sill, as I could feel air seeping in.  I can't say how great this stuff is.  I've got it on all my windows.  It's very easy if you need to adjust it and taking it off is a breeze. You can peel it off in whayever is needed....thin, medium or thick pieces.  It's inexpensive as well!  I needed to write this review for you because I believe when you're going to buy a product...it's nice to hear from someone who has used it if it's good or not. Again, great great product and price!!

## Customer Reviews

### ⭐⭐⭐⭐⭐ Good sealing, very helpful in difficult conditions but a little be temperature sensitive
*by B***. on 22 February 2023*

Good sealing, very helpful in difficult conditions but a little be temperature sensitive so when I tried to apply it during a wind storm, cloudy, sunless day at 47º F, it was stiff and stuck to my fingers more than it stuck to the window frame. I still recommend it really did stop the significant cold air leaks (and small leaks as well) which is exactly what we wanted, When the temperature is a little bit warmer its easy to apply but when the metal window frame got down to 47º F in high winds, it got still and did not stick to the metal frame so much, I could still push it into place into the grooves that were laking a huge amount of air. NOTE: Even a tiny hole can leak a massive amount of air, so its best to use more and push it into every possible crevice to trite catch all the possible leaks. When the window temperature is cld and the caulk doesn't want to stick to the cold metal frame, it will tend to stick to your fingers so push in to the slot/crevice then slide or twist your finger to release the caulk (don't worry it washes easily off you're fingers so push it as hard as necessary to get it to stick to the frame). You will notice that once you install it that when it's cold it will harden, don't worry, it still seals the window and keeps the drafts out. When the temperature rises then it will soften again and if you need to you can then work it into the gap/crevice some more. Although its listed as 45 feet which sounds like a lot, keep in mind that it comes in 5 rows, you can tear off 1, 2, 3, 4 or 5 strands and install them, so very often you will use more than 1 strand (I often used 3 or 4 strands) so I was only able to seal one and a half standard sided windows (which is all I added to do anyway), at its low price its certainly worth buying more if you need it, use plenty so it seals your windows properly. I would give it a 5 start rating other than a slight challenge with installing it at cold temperatures (which it still got installed, it just took more effort, that was worth it).

### ⭐⭐⭐⭐⭐ If you need it, it’s a good, easy-to-use product
*by �***R on 1 May 2020*

I had floor-to-ceiling gaps on both sides of my stone fireplace where it met my wood-paneled walls. The gaps ranged from 1/16” to 1/4” wide. The gaps never bothered me until I saw a roach exit the gap on one side of the fireplace, zip across the stone, and then disappear into the gap on the other side. Yuck, can’t have that. A few knowledgeable people advised me to apply a clear silicone bead, but I was reluctant because I figured I’d mess it up somehow and then I’d be upset that it didn’t look good. It was sheer serendipity that I came across this product while wasting time on Amazon. The product is 90’ in length made of 8 strips across that can easily be pulled apart. In my case, I peeled off a 3 strip section (which is approximately 1/2” wide (depending on how you squish it) and, starting at the ceiling, worked my way down, using my fingers to push the product along the gap and over and around the stone (the gap is very bumpy and uneven). The biggest issue I had was holding the big roll as I rolled it down the wall. In the end, I was very happy with the seal, the overall look, how easy it was to do, how unmessy it was to work with, and the brown color that complements the paneling. I attached a photo of what it looks like up close. It actually looks much better in person because the caulk lies in recessed corners on both sides of the fireplace; it just looks like dark corners without all the detail of the up-close photo. - Easy to remove? Yes, in the beginning and for at least 1 year (in my experience). I don’t know how easy it is to remove when it dries out over time. - How long will it last? I don’t know. So far, it’s been 1 year and it’s still adhering and still looking good. - Will it damage the wood paneling? I don’t know. I guess I’ll find out whenever it deteriorates enough that I have to remove it. - Will it leave residue on the stone? See answer above. I’m thinking I should probably remove it before it hardens and re-bead the gap with fresh product. For the price, ease of use, and color, it was a good solution for my problem. I think it probably looks better than the silicone would have, too. ___________________________ Update: December 2024 (6 years after putting up the product): A small portion (about 2 ft starting at the ceiling) of the caulk fell off, but the rest is still holding fairly well. I can tell it's dry in places because there's slight movement in places down the bead. So, I replaced the bead on once side of the fireplace and will eventually get around to doing the other. Thus, it held up for a solid 6 yrs. I don't know if that's good or bad, but it seems decent to me. The caulk did not damage my wood paneling, did not damage the stone of the fireplace, did not leave any residue anywhere, and was easy to remove.

### ⭐ A éviter
*by B***U on 2 September 2026*

Acheté pour combler une fente entre le mur et la menuiserie. Les cordons se cassent et n'adhèrent pas. Le colis était aussi écrasé. soit le produit est trop vieux soit il n'est pas efficace. Je ne recommande absolument pas.

## Frequently Bought Together

- Frost King B2 Mortite Fingertip Caulking Cord, 1/8" x 90 ft, Grey
- XFasten Transparent Window Weather Sealing Tape, 2-Inch x 30 Yards (50.8mm x 27.43m), Clear Window Draft Isolation Sealing Film Tape, No Residue
- Transparent Window Weather Sealing Tape 2 Inch x 33 FT Weather Stripping Residue-Free Clear Window Insulation Tape for Doors Windows and Shower Glass Gaps

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*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-09-28*