Gray North 12×12 to 18×8 Center Trunk Transition S&D MFG#188X1212-81CSD

12×12 to 18×8 Center Trunk Transition – Slip & Drive

Gray North | MFG# 188X1212-81CSD | Galvanized Steel HVAC Fitting

This rectangular trunk transition is designed to convert duct size from 12″ x 12″ to 18″ x 8″ in HVAC supply and return trunk systems.

The centered (CTR) configuration maintains balanced airflow alignment while changing trunk dimensions, helping reduce turbulence and static pressure loss.

Manufactured from heavy-duty galvanized steel, this fitting features Slip & Drive (S&D) connections for fast, secure field installation.

Key Features:

• Transitions from 12″ x 12″ to 18″ x 8″

• Centered Design (CTR)

• Slip & Drive Connection

• Pittsburgh Seam Construction

• Heavy-Gauge Galvanized Steel

• Ideal for Trunk Line Modifications

Common Applications:

• Main supply trunk resizing

• Return air trunk transitions

• Commercial HVAC installations

• Residential trunk line upgrades

Pairs with rectangular trunk duct sections, elbows, and take-offs for complete duct system fabrication.

Ideal for HVAC contractors and mechanical installers.

Product details

Part / SKU	188X1212-81CSD

Package includes

• Gray North 12×12 to 18×8 Center Trunk Transition S&D MFG#188X1212-81CSD

Included components and any stated pack quantity are as described in this listing. Optional accessories shown separately are sold separately unless expressly included above.