... heavy-duty air filter DJGT-600 Full-automatic rotary paper pleating production lineConsists1, Automatic de-coiler2, Pre-slitter ... especially suitable for Heavy-duty air filters.4, Filter paper is automatically counted, pleated, pre-heated and formed. ... which made from stainless steel, assures the paper evenly & smoothly pleated.6, Computer controlling, easy operation. filter paper pleating machines