Wet laid, nonwoven, fibrous mats suitable for making MERV 6 or higher filters, and methods of making the nonwoven mats are disclosed. The mats include a blend comprising a major portion of glass fibers and a minor portion of man-made polymer fibers, such as polyester fibers, the fibers being bound together with a cured binder having a Tg in the range of about minus 30 to about 50 degrees C. The mats are pleated prior to assembling the filter in conventional manner. The only fibrous mat in the filters is wet laid fibrous nonwoven mat and the pleated filter media needs no other means of support in the filter frame.