#3 FILTERS  A .5 micron pad used for final filtration.  

#2 FILTERS   Pads are rated nominally, which means that the rating is an average of all of the sizes of pores in the media. Fine pads are rated to 2 microns nominal, and are appropriate for polish filtration of red and white wines. Typically the finest filtration a red wine will go through.

#1 FILTERS Coarse pads are rated to 7 microns nominal, and are appropriate for initial clearing of red and white wines when particularly cloudy. With a nominal rated pad some material below the rating will be trapped and some material above the rating will be allowed to pass, the 7 micron represent an average.