--- product_id: 303805407 title: "Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray" brand: "red devil" price: "¥11025" currency: JPY in_stock: true reviews_count: 5 category: "Red Devil" url: https://www.desertcart.jp/products/303805407-red-devil-0846dx-f-seal-181-fiber-reinforced-water-based store_origin: JP region: Japan --- # Fast-drying & low VOC formula Fiber-reinforced for leak-free HVAC UL 181 A-M & B-M certified Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray **Brand:** red devil **Price:** ¥11025 **Availability:** ✅ In Stock ## Summary > 🔧 Seal smart, save energy, and never sweat the leaks again! ## Quick Answers - **What is this?** Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray by red devil - **How much does it cost?** ¥11025 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/303805407-red-devil-0846dx-f-seal-181-fiber-reinforced-water-based) ## Best For - red devil enthusiasts ## Why This Product - Trusted red devil brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Seal Like a Pro:** Fiber-reinforced formula guarantees airtight HVAC systems, boosting energy efficiency and comfort. - • **Certified Confidence:** UL 181 A-M & B-M certification means trusted performance on all duct types—metal, fiberglass, or flex. - • **Fast & Safe Application:** Quick-drying with low VOCs for a safer, cleaner workspace—perfect for sensitive environments. - • **Industry-Leading Standards:** Exceeds SMACNA Pressure and Sealing Classes, delivering professional-grade reliability every time. - • **Built to Brave the Elements:** Weather-resistant durability ensures your seal holds strong indoors and outdoors, no matter the conditions. ## Overview Red Devil 0846DX F-Seal 181 is a premium fiber-reinforced, water-based duct sealant designed for superior leak-proof sealing of HVAC systems. UL 181 A-M & B-M certified, it works seamlessly on metal, fiberglass, and flexible ducts. Its weather-resistant, fast-drying, and low VOC formula ensures durable indoor/outdoor performance while exceeding industry standards for pressure and sealing. Trusted by professionals and DIYers alike, it’s the go-to solution for energy-efficient, reliable HVAC sealing. ## Description Red F-Seal 181 is a specially formulated fiber reinforced water based duct sealant/mastic for indoor/outdoor use. Suitable for pressure sealing all types of HVAC duct systems including metal, fiberglass ductboard and flexduct. Made in USA. FEATURES: LEED EQ 4.1 Compliant Indoor/Outdoor Excellent Adhesion Excellent Flexibility Low VOC USE ON: Metal and Flexible Ducts Vents Air Conditioners HVAC Appliances SPECIFICATIONS: UL 181 A-M & B-M certified and can be used on all types of HVAC ductwork. ABOUT RED : Red is still a privately-owned family business with state-of-the-art manufacturing facilities in Pryor, Oklahoma. Click on the Red link at the top of this page to visit our Brand Store. Review: Works great - I sealed my ducts in the basement and now my basement is not that cold anymore in the summer when my A/C is running. Now I know how much money I had wasted for the last 10 years :-). Now my upstair has more air flow and cooler. Review: Good for all around applications - I bought this to fill a small ducting leak in my a/c but also applied it to my house when doing stucco repairs on holes left behind by the last sprinkler timer on the outside of my house. It dried perfectly and painted over very well. I docked it a star because I noticed the canister developed a leak while dispensing the contents on the first use. I wasn't using much pressure with the caulk gun so not sure why it happened so easily. However, it did seal itself so I can continue using it. The packaging needs some improvement, though. ## Features - SUPERIOR SEALING: Fiber-reinforced formula ensures leak-free HVAC systems, improving energy efficiency and performance - VERSATILE APPLICATION: UL 181 A-M & B-M certified for use on all types of HVAC ductwork, including metal, fiberglass, and flexible ducts - INDOOR/OUTDOOR DURABILITY: Weather-resistant sealant withstands various conditions, making it ideal for both interior and exterior use - FAST-DRYING & LOW VOC: Quick application and reduced drying time, with low volatile organic compounds for safer use in sensitive environments - EXCEEDS INDUSTRY STANDARDS: Surpasses all SMACNA Pressure and Sealing Classes, ensuring top-quality performance for your HVAC systems ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B01I7JVUR2 | | Best Sellers Rank | #148,897 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #226 in Heating & Cooling Ducting Products | | Brand | Red Devil | | Brand Name | Red Devil | | Color | Gray | | Compatible Material | Fiberglass, Metal | | Customer Reviews | 4.4 out of 5 stars 1,278 Reviews | | Global Trade Identification Number | 00075339003480 | | Included Components | Duct Sealant | | Item Dimensions | 5.1 x 5.1 x 28.6 centimeters | | Item Form | Liquid | | Item Type Name | Water Based Duct Sealant | | Item Weight | 1.05 Pounds | | Item dimensions L x W x H | 5.1 x 5.1 x 28.6 centimeters | | Item weight | 1.05 Pounds | | Manufacturer | Red Devil | | Material | White | | Material Type | White | | Model | 0846DX | | Number of Items | 1 | | Number of Packs | 1 | | Part Number | 0846DX | | Style | F Seal | | Style Name | F Seal | | Surface Recommendation | Metal | | UPC | 075339003480 | | Unit Count | 1 Count | | Water Resistance Level | Water Resistant | | Water resistance level | Water Resistant | ## Product Details - **Brand:** Red Devil - **Item dimensions L x W x H:** 17.8 x 17.8 x 20.3 centimeters - **Item weight:** 1 Pounds - **Material:** Silicone - **Style:** 1 - Pack ## Images ![Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray - Image 1](https://m.media-amazon.com/images/I/51GL4IS8GML.jpg) ![Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray - Image 2](https://m.media-amazon.com/images/I/61DR9w5x7fL.jpg) ![Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray - Image 3](https://m.media-amazon.com/images/I/61wXviPRg2L.jpg) ![Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray - Image 4](https://m.media-amazon.com/images/I/61g4OiMBuXL.jpg) ![Red Devil 0846DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 10.1 oz, Gray - Image 5](https://m.media-amazon.com/images/I/71BJyuDkMZL.jpg) ## Available Options This product comes in different **Size, Style** options. ## Questions & Answers **Q: Is the "F" in the bucket like a liquid (brushable) or more like a paste?** A: It's not quite like a paste but it's not liquidity either and doesn't drip so you can put it on thick. I love this stuff, not much of a odor as well. I used a cheap chip brush to spread it. **Q: I'm redoing all the flex ductwork (insulated kind) in a crawl space. should i use the d our f sealant ?** A: You could use either one. Both are perfect for what you are doing, but I would use the F-Seal because it has fibers in it. **Q: Is this safe to use and will it work on gas dryer duct work joints (inside the fittings and outside)?** A: Sorry, this should not be used on a dryer. It is for HVAC only. Thanks. **Q: How long do I need to wait before turning on the A/C after application?** A: Hi, you should wait 24 hours. Thanks.... ## Customer Reviews ### ⭐⭐⭐⭐ Works great *by H***. on 26 July 2020* I sealed my ducts in the basement and now my basement is not that cold anymore in the summer when my A/C is running. Now I know how much money I had wasted for the last 10 years :-). Now my upstair has more air flow and cooler. ### ⭐⭐⭐⭐ Good for all around applications *by S***G on 2 October 2020* I bought this to fill a small ducting leak in my a/c but also applied it to my house when doing stucco repairs on holes left behind by the last sprinkler timer on the outside of my house. It dried perfectly and painted over very well. I docked it a star because I noticed the canister developed a leak while dispensing the contents on the first use. I wasn't using much pressure with the caulk gun so not sure why it happened so easily. However, it did seal itself so I can continue using it. The packaging needs some improvement, though. ### ⭐⭐⭐⭐⭐ great buy *by J***T on 11 March 2025* great buy great buy great buy ## Frequently Bought Together - Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 1 Gallon, Gray, Made in USA - Pro Grade - Chip Paint Brushes - 12 Ea 2 Inch Chip Paint Brush Light Brown --- ## 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.jp/products/303805407-red-devil-0846dx-f-seal-181-fiber-reinforced-water-based](https://www.desertcart.jp/products/303805407-red-devil-0846dx-f-seal-181-fiber-reinforced-water-based) --- *Product available on Desertcart Japan* *Store origin: JP* *Last updated: 2026-09-17*