... filter Material:cotton 2.Lenght:10",20",30",40" filter cartridge 3.Diameter:Out 65-70mm,inner:28-30mm wrap filter ... the fields of food&beverage, pharmaceutical industry.Activated carbon filter cartridge is made from the premium fruit shellcarbon and coal activated ... ) 20inch: 15PCS/CTN (65x42x28cm) 30inch: 15PCS/CTN (89x42x28cm) wrap filter cartridge cotton filter cartridge for water treatment