Lennox 78L01 Fan Blade 320788-702 Is this the correct part

Is this the correct part for a 4-inch venting setup

As a direct OEM replacement valve for discontinued part numbers 81660145U and 81660282

it utilizes a 1-3/8" x 2-1/4" coiled sensing bulb to ensure high sensitivity and accurate thermal response

Durable construction: Rugged cast iron and aluminum assembly ensures longevity in harsh mechanical room environments

A compromised manifold can cause uneven burner firing

Lennox 78L01 Fan Blade 320788-702 Is this the correct partThe Lennox 78L01 Fan Blade is a critical OEM replacement component designed for high efficiency outdoor condensing units and heat pumps. This 18 inch diameter condenser fan blade features a robust 4 blade configuration with a 26 degree pitch, engineered to provide optimal CFM while maintaining low acoustic signatures during high load operations. Built for precision, the 78L01 utilizes a 1 2 inch bore diameter and is indexed for clockwise (CW)