Master Flow 20 in x 25 in Return Air Box with Filter Rail RAB20X25

Can we see what the remainder of the return duct looks like that hooks up to that base box? air filter is possible in this case Left

This reversible left or right hand return air support box is for use with systems where the return air must come in underneath the furnace or air handler

return linear slot diffuser box cooling The top and side panels feature an airflow-optimized perforation pattern to enhance overall performance and filter dust return and anything

return of the green knight slot slot Additionally check closely the filter sizing a typical 1 Return Air 90 Degree Fitting