Southwark Metal 21r82016 End Cap R8 20x16 in

Product Description

The SOUTHWARK METAL 21r82016 is a Model 21 duct end cap with R8 insulation, sized at 20 inches by 16 inches. It is fabricated from hot-dipped galvanized steel conforming to ASTM A653 CS Type B at 26 gauge. The S-Lock drive-type connection provides a secure mechanical fit for rectangular ductwork terminations. This end cap is used to seal the open end of an insulated duct run and is installed by sheet metal workers and HVAC technicians during new construction or duct modification work.

This end cap is suited for residential and light commercial HVAC ductwork applications where insulated rectangular duct systems require a sealed termination. The R8 insulation rating makes it appropriate for installations in unconditioned spaces such as attics, crawlspaces, and exterior wall chases where thermal performance requirements are higher. It connects using an S-Lock drive-type joint and is also available with S-cleat fastening. Insulation options of R4 and R6 are available in the same model family for applications with different thermal requirements.

Key Features

• Hot-dipped galvanized steel per ASTM A653 CS Type B for corrosion resistance
• 26 gauge steel construction for rigid, durable duct termination
• R8 insulation rating suitable for unconditioned space installations
• S-Lock drive-type connection for a secure mechanical fit
• Available with S-cleat fastening as an alternative connection method
• Compatible insulation options include R4 and R6 in the same model family

Compatibility

Designed as an OEM-style replacement and standard component for Model 21 insulated rectangular ductwork systems using S-Lock drive connections. Also available in R4 and R6 insulation variants within the same product family.

Installation Notes

Installation is performed by licensed sheet metal workers or HVAC technicians. Shut down the air handling system before making duct modifications or installing end caps. Ensure the S-Lock or S-cleat connection is fully seated and sealed per applicable SMACNA ductwork standards. Follow local mechanical codes for duct insulation continuity requirements at termination points.

Technical Specifications

• Model: 21
• Dimensions: 20 inches x 16 inches
• Insulation Rating: R8
• Material: Hot-Dipped Galvanized Steel
• Material Standard: ASTM A653 CS Type B
• Gauge: 26
• Connection Type: S-Lock Drive
• Unit of Measure: Each

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 21r82016