Threw a couple of these BWD/NIEHOFF (Service-Pro) M2500 filters in on a recent order. Cost was $1.12ea and was a "Wholesaler Closeout". Filter is dated 4/13/16 and seems to be recent production "Made in China" jobber filter. Has a Nitrile ADBV that is pretty pliable and top spring load bypass valve.
Overall construction seems decent given the price point. Media I am sure is cellulose but does seem to pretty sturdy and not prone to tearing when I dissected the filter. Rough math gives appox. 113 square inches of usable media area with 58 pleat counted.
Overall construction seems decent given the price point. Media I am sure is cellulose but does seem to pretty sturdy and not prone to tearing when I dissected the filter. Rough math gives appox. 113 square inches of usable media area with 58 pleat counted.