Duct Tee For Nominal Duct Diameter 4 in Material Steel Overall Length 8 7/8 in Product Type Tee Maximum Pressure Rating Not Applicable Maximum Temperature Rating 550 Degrees F Shape Tee End Type Snap Lock Coupling Gas Appliance Category Category I Maximum Airflow Not Applicable Inside Diameter 4 in Color Silver Connection Type Interlocking Bracket For Duct Shape Round Standards AGA HUD NBC NFPA UBC UL Certified UL 441 Series ET/RT