--- product_id: 303805407 title: "Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 1 Gallon, Gray" brand: "red devil" price: "400.35 DT" currency: TND in_stock: false category: "Red Devil" url: https://www.desertcart.tn/products/303805407-red-devil-0841dx-f-seal-181-fiber-reinforced-water-based store_origin: TN region: Tunisia --- # Fast-drying & low VOC formula Fiber-reinforced for leak-free HVAC UL 181 A-M & B-M certified Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 1 Gallon, Gray **Brand:** red devil **Price:** 400.35 DT **Availability:** ❌ Out of Stock ## Summary > 🔧 Seal smart, save energy, and never sweat the leaks again! ## Quick Answers - **What is this?** Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 1 Gallon, Gray by red devil - **How much does it cost?** 400.35 DT with free shipping - **Is it available?** Currently out of stock - **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/303805407-red-devil-0841dx-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 Devil 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 DEVIL: Red Devil is still a privately-owned family business with state-of-the-art manufacturing facilities in Pryor, Oklahoma. Click on the Red Devil link at the top of this page to visit our Brand Store. ## Features - High quality, fiber reinforced - UL 181 a-m & b-m certified - Can be used on all types of HVAC ductwork - Interior/exterior - Made in the USA ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B01I7JVUO0 | | ASIN | B01I7JVUO0 | | Best Sellers Rank | #92,991 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #125 in Heating & Cooling Ducting Products | | Brand Name | Red Devil | | Color | Gray | | Compatible Material | Plastic | | Customer Reviews | 4.4 4.4 out of 5 stars (1,166) | | Customer reviews | 4.4 4.4 out of 5 stars (1,166) | | Date First Available | 11 July 2016 | | Global Trade Identification Number | 00075339003466 | | Included Components | Duct Sealant | | Item Dimensions | 17.8 x 17.8 x 20.3 centimeters | | Item Form | Paste | | Item Type Name | Water Based Duct Sealant, 1 Gallon | | Item Weight | 1 Pounds | | Item model number | 0841DX | | Manufacturer | Red Devil | | Manufacturer | Red Devil | | Material Type | Silicone | | Model | 0841DX | | Number of Items | 1 | | Number of Packs | 1 | | Part Number | 0841DX | | Product Dimensions | 17.78 x 17.78 x 20.32 cm; 453.59 g | | Style Name | 1 - Pack | | Supported Standards | UL 181 a-m, UL 181 b-m | | Surface Recommendation | Duct | | UPC | 075339003466 | | Unit Count | 128 Milliliters | | 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 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 1 Gallon, Gray - Image 1](https://m.media-amazon.com/images/I/718Qkc+7HiL.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.... ## 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.tn/products/303805407-red-devil-0841dx-f-seal-181-fiber-reinforced-water-based](https://www.desertcart.tn/products/303805407-red-devil-0841dx-f-seal-181-fiber-reinforced-water-based) --- *Product available on Desertcart Tunisia* *Store origin: TN* *Last updated: 2026-10-29*