Woodstock 4in x 2-1/2in Y-Fitting D3996

"Woodstock 4in x 2-1/2in Y-Fitting D3996. This stepdown increases air velocity near the machine where it's needed most. This YFitting has a 21/2 diameter lateral port for connecting to a 4 diameter line. Package Contents: Woodstock x 2-Y-Fitting Woodstock D3996 4in x 2-1/2in Y-Fitting"