Industrial-grade galvanized steel end caps engineered to seal duct openings completely — preventing air leakage, maintaining system pressure, and protecting ductwork from dust and debris. Available in 3″ to 36″ diameters.
SIDCO End Caps are manufactured using 22-gauge G60 galvanized or Paintgrip steel to provide a complete, durable seal at the open end of any spiral duct. Featuring sealing gaskets to minimize air leakage, these end caps are available in die-stamped sizes from 3″ to 16″ and fabricated sizes from 18″ to 36″ — covering the full range of commercial and industrial HVAC applications.
Each end cap is engineered for exact dimensional fit — ensuring a flush, gapless seal on any spiral duct diameter we manufacture.
Smaller sizes are die-stamped for tight tolerances. Larger sizes (18″+) are roll-fabricated for structural strength at scale.
Every end cap is checked for fitment, seam integrity, and coating quality before leaving our Memphis facility.
Stocked in Memphis, TN for rapid fulfillment. Order online or by phone — delivered when your project needs it.
Sealing unused duct branch openings in offices, retail spaces, and commercial buildings to maintain balanced airflow.
Closing off duct terminations in warehouses and manufacturing plants where system pressure integrity is critical.
Protecting open duct ends during construction phases — keeping dust, debris, and moisture out before installation is complete.
Capping off decommissioned duct branches during HVAC retrofits and system redesigns without full duct removal.
Maintaining conditioned-air pressure in sealed zones by blocking unused supply and return openings permanently.
Terminating exhaust duct runs cleanly in kitchen ventilation, lab fume, and general exhaust duct networks.
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