--- product_id: 532575340 title: "Rolled Mastic Duct Sealants Foils 3'' X100" brand: "hardcast" price: "€ 156.68" currency: EUR in_stock: true reviews_count: 5 category: "Hardcast" url: https://www.desertcart.at/products/532575340-rolled-mastic-duct-sealants-foils-3-x100 store_origin: AT region: Austria --- # 3'' x 100' length for extensive coverage UL 181B-FX flame spread classified High adhesion foil for metal ductwork Rolled Mastic Duct Sealants Foils 3'' X100 **Brand:** hardcast **Price:** € 156.68 **Availability:** ✅ In Stock ## Summary > 🔥 Seal smart, save energy, and stay safe with every roll! 🛠️ ## Quick Answers - **What is this?** Rolled Mastic Duct Sealants Foils 3'' X100 by hardcast - **How much does it cost?** € 156.68 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.at](https://www.desertcart.at/products/532575340-rolled-mastic-duct-sealants-foils-3-x100) ## Best For - hardcast enthusiasts ## Why This Product - Trusted hardcast brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Long-Lasting Adhesion:** Sticks like premium roofing tape for reliable performance - • **Made in USA Quality Assurance:** Trusted craftsmanship for professional results - • **UL Classified Flame Spread Safety:** Certified for safe indoor/outdoor use - • **Precision Seal for Energy Efficiency:** Stops air leaks to save on HVAC costs - • **Durable Foil with Superior Flexibility:** Molds over sharp metal edges without ripping ## Overview Rolled Mastic Duct Sealants Foils 3'' X100 is a UL-classified, high-adhesion silver foil tape designed for sealing HVAC ductwork. Measuring 3 inches by 100 feet, it offers durable, flexible coverage that molds over sharp metal edges without tearing. Ideal for indoor and outdoor use, this flame spread rated tape ensures energy efficiency by preventing air leaks and is proudly made in the USA for professional-grade reliability. ## Description G80-192 and G80-193 are red printed and UL classified for flame spread G80-325 and G80-326 are UL 181B-FX listed for use on flexible duct systems G80-194 and G80-195 are for higher pressure applications up to 10" w.g. Application: Indoor/Outdoor; Carton Qty.: 16; Description: Silver Foil Grip — Printed; Mfg. #: AFG-1402-3; Size: 3" x 100' Review: This has to be the world’s stickiest tape. Very durable. - This has to be the world‘s stickiest tape. This very heavy, thick and durable foil tape sticks to everything and is very permanent once supplied. If you accidentally fold it upon itself, fuggeddaboudit, you won’t get it apart. This is perfect for sealing duct board or other items such as flex duct to a takeoff boot or similar such applications. This is a large roll also. 100 linear feet, so it might be expensive at first glance, but it really isn’t. It goes a long way. Review: Fixed a big issue with my HVAC efficiency - Last summer was hot in Central Texas, and my utility bill was sky high during the hottest months. This year I renewed the electric service contract and prices are naturally much higher, so I decided to do some deep investigation into why the HVAC wasn't performing as well as I expected it to. A couple of rooms at the end of the duct runs were always far hotter than the rest, even though the air temperature was the right temp coming out of the register. Fast-forward and what I discovered was the mastic on the downstairs evaporator coil box (both furnace units in the attic) had become separated from the supply and return boxes/plenum, who knows for how long. It was essentially blowing a significant amount of cold air into the attic instead of the house. This made the upstairs unit stay on 24/7 during hot months since it was essentially trying to cool the entire home. I cleaned the surfaces (well enough...I won't claim to have made it as clean as recommended) and slapped this rolled mastic tape on all affected areas. Also re-arranged some of the duct work that had sagged out of spec due to the home builders not properly stretching the flexduct when installing. Then I used more of this mastic tape on the upstairs furnace and sealed things up nice and tight. A/C issues solved! Rooms at the end of the runs are the same temps as the rest now, and my A/C runs about 40% less on those super hot days! Every homeowner should own a roll of this mastic tape and understand how such an inexpensive item can affect such an expensive system. ## Features - Package Dimensions: 18.034 cms (L) x 17.272 cms (W) x 18.034 cms (H) - Product Type: Tools - Package Quantity: 1 - Package Weight: 4.03 lbs ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B005ZVJM1M | | Batteries Required? | No | | Batteries included? | No | | Colour | Sliver | | Customer Reviews | 4.7 4.7 out of 5 stars (220) | | Date First Available | 26 Oct. 2011 | | Item Package Quantity | 1 | | Item Weight | 1.35 kg | | Item model number | 638532806335 | | Manufacturer | hardcast | | Material | Foil Tape | | Measurement System | Imperial | | Part Number | 638532806335 | | Product Dimensions | 20.32 x 20.32 x 7.62 cm; 1.35 kg | | Special Features | Printed | | Style | Compact | ## Images ![Rolled Mastic Duct Sealants Foils 3'' X100 - Image 1](https://m.media-amazon.com/images/I/61LFil37TSL.jpg) ![Rolled Mastic Duct Sealants Foils 3'' X100 - Image 2](https://m.media-amazon.com/images/I/61OK5FOW4PL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ This has to be the world’s stickiest tape. Very durable. *by M***O on 5 May 2026* This has to be the world‘s stickiest tape. This very heavy, thick and durable foil tape sticks to everything and is very permanent once supplied. If you accidentally fold it upon itself, fuggeddaboudit, you won’t get it apart. This is perfect for sealing duct board or other items such as flex duct to a takeoff boot or similar such applications. This is a large roll also. 100 linear feet, so it might be expensive at first glance, but it really isn’t. It goes a long way. ### ⭐⭐⭐⭐⭐ Fixed a big issue with my HVAC efficiency *by S***X on 15 July 2024* Last summer was hot in Central Texas, and my utility bill was sky high during the hottest months. This year I renewed the electric service contract and prices are naturally much higher, so I decided to do some deep investigation into why the HVAC wasn't performing as well as I expected it to. A couple of rooms at the end of the duct runs were always far hotter than the rest, even though the air temperature was the right temp coming out of the register. Fast-forward and what I discovered was the mastic on the downstairs evaporator coil box (both furnace units in the attic) had become separated from the supply and return boxes/plenum, who knows for how long. It was essentially blowing a significant amount of cold air into the attic instead of the house. This made the upstairs unit stay on 24/7 during hot months since it was essentially trying to cool the entire home. I cleaned the surfaces (well enough...I won't claim to have made it as clean as recommended) and slapped this rolled mastic tape on all affected areas. Also re-arranged some of the duct work that had sagged out of spec due to the home builders not properly stretching the flexduct when installing. Then I used more of this mastic tape on the upstairs furnace and sealed things up nice and tight. A/C issues solved! Rooms at the end of the runs are the same temps as the rest now, and my A/C runs about 40% less on those super hot days! Every homeowner should own a roll of this mastic tape and understand how such an inexpensive item can affect such an expensive system. ### ⭐⭐⭐⭐⭐ EASY to use *by C***. on 11 September 2026* Hardcast mastic tape is the best because the backing comes off easily and doesn’t slow you down struggling to remove it like SureTape does. And it’s super sticky, strong, durable. ## Frequently Bought Together - Rolled Mastic Duct Sealants Foils 3'' X100 - Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant, 1 Gallon, Gray, Made in USA - Hardcast 304099 Foil-Grip 1402 Mastic Duct Sealant 2" x 100' --- ## 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.at/products/532575340-rolled-mastic-duct-sealants-foils-3-x100](https://www.desertcart.at/products/532575340-rolled-mastic-duct-sealants-foils-3-x100) --- *Product available on Desertcart Austria* *Store origin: AT* *Last updated: 2026-11-07*