Metalcraft att18 Air Tite Take-off 18 Inch Flanged Steel

Product Description

The METALCRAFT att18 is an Air Tite take-off fitting designed for low-pressure sheet metal ductwork systems commonly found in residential and light commercial HVAC installations. Built from 28-gauge galvanized steel with a hot-dipped galvanized finish, this round fitting measures 18 inches and connects via a flanged connection for a secure, airtight seal. The ATT Series design seats directly into the main duct trunk and provides a reliable branch tap point for supply air distribution. HVAC installers and sheet metal mechanics use these fittings during new construction and retrofit duct fabrication work.

This fitting is suited for use in forced-air heating and cooling distribution systems where a round branch takeoff is needed from a rectangular or flat-oval trunk duct. The flanged connection style simplifies installation and helps maintain consistent airflow paths throughout the duct system. The hot-dipped galvanized steel construction resists corrosion in attic, crawlspace, and mechanical room environments where moisture and temperature swings are common.

Key Features

• 28-gauge galvanized steel construction for durability in varied installation environments
• Hot-dipped galvanized finish provides corrosion resistance
• Flanged connection type allows for secure, airtight duct attachment
• 18-inch fitting size accommodates large-diameter branch supply runs
• Round shape compatible with standard round flex duct and rigid spiral pipe
• ATT Series design for consistent fitment and reliable air sealing

Compatibility

Designed as an OEM-style sheet metal fitting for use with standard round branch duct takeoff applications in residential and light commercial forced-air HVAC systems.

Installation Notes

Installation should be performed by a licensed HVAC technician or qualified sheet metal mechanic. Power down and lock out the air handling unit before cutting into an existing trunk duct. Secure the flanged connection with sheet metal screws and seal all seams with UL 181-rated mastic or foil tape per local mechanical code requirements. Follow SMACNA duct construction standards and applicable local codes when sizing and locating branch takeoffs.