We remain fully operational. Our teams are working around the clock to ensure your deliveries continue safely.
DOWNLOAD THE APP
Customer Services
Copyright © 2025 Desertcart Holdings Limited
DOWNLOAD THE APP
🔧 Seal smart, sound silent, and stay ahead of the HVAC game!
Hardcast’s 304156 1 Gallon Duct Seal 321 is a professional-grade, silicone-based duct sealant designed for durable, flexible sealing of HVAC ductwork. With a large 128 fl oz volume, it excels at blocking air leaks, reducing noise by securing sound-absorbing materials, and preventing pest intrusion. Its compact, easy-to-apply formula is optimized for rubber and similar surfaces, making it an essential tool for managers and contractors aiming for efficient, quiet, and pest-free ventilation systems.
| ASIN | B00E0Q4Y6G |
| Batteries Included? | No |
| Batteries Required? | No |
| Best Sellers Rank | #272,570 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #692 in Hardware Sealers |
| Brand | Hardcast |
| Color | gray |
| Customer Reviews | 4.6 4.6 out of 5 stars (18) |
| Date First Available | July 18, 2013 |
| Included Components | DS-321-GRAY-4-1 GAL |
| Is Discontinued By Manufacturer | No |
| Item Form | Liquid |
| Item Package Quantity | 1 |
| Item Weight | 10.56 pounds |
| Item model number | 304156 |
| Manufacturer | Hardcast |
| Material | Silicone |
| Number of Items | 1 |
| Package Dimensions | 8.11 x 7.76 x 7.52 inches |
| Part Number | 304156 |
| Style | Compact |
| Surface Recommendation | Rubber or similar surfaces |
| UPC | 063853280050 |
| Unit Count | 128.0 Fluid Ounces |
| Water Resistance Level | Not Water Resistant |
A**C
Great product for sealing your ductwork!
This duct seal is fantastic! I use it to seal any penetrations, seal sheet metal corners to keep pests out of the tiny openings and most importantly I use it to glue in noise cancelling cloths inside the ductwork to reduce the sound of the metal moving when the evaporative cooler starts up.
S**F
Cool
👍
J**N
Best stuff
Works perfectly
S**G
Great stuff
I needed this to seal some rooftop duct work it worked just as good now as it did 20 years ago when I was doing HVAC. it was listed at a fair price
H**T
Wonderful quality
Wonderful quality , easy to apply
T**S
ease.
great stuff, easy to apply.
J**R
Five Stars
good sealer and prevents air leaks .
Trustpilot
3 weeks ago
1 month ago