Adopting the way of multi-stage filtration, the series are simple in operation and convenient in maintenance, which are suitable to remove the impurities out of the oil, such as insulating oil, turbo-oil, machine oil and hydraulic oil etc. \n\nthey can be fitted with different types of filter-assemblies. with the advantages that low cost and high filtering accuracy. they are the latest substitution products of the series of plate-frame pressure oil-filter.