RCD #6 Mastic Duct Sealant
by RCD Corporation
Last updated Mar 29, 2026 · 2 revisions
Fiber-reinforced, UL-listed water-based mastic preferred by professional HVAC and weatherization contractors nationwide.
Highlights
Media
About This Product
RCD #6 Mastic is a white, flexible, water-borne duct sealant used to permanently seal joints and seams of flexible air ducts, ductboard, sheet metal ducts, and thermal insulation. Available in 10.6 oz cartridges and 1-gallon pails, it meets all SMACNA seal classes and is the industry standard for residential duct sealing.
Capabilities
How this product is delivered and what's included out of the box.
- Mobile app
- Not available
- Free trial
- No
- Free tier
- No
- Public API
- No
- Deployment
- On Premise
FSH Score Breakdown
Customer Reviews
Features
Compliance & Safety2features
Pricing
- Model
- Custom
- Starting at
- $37
- Notes
- 1-gallon pail ~$37-45 depending on retailer (Conservation Mart $36.94, URI $44.56). Also available in 10.6 oz tube and 2-gallon pail. Available on Amazon, HVAC wholesale distributors, and specialty retailers.
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