7 Filters for the purification of air, gases, and fluids as parts of motors, engines, and construction, mining, and agricultural machines; filter systems comprising filter housing and replaceable filter elements as parts of motors, engines, and construction, mining, and agricultural machines; filter elements for the aforesaid filters and filter systems; liquid filters as parts of motors, engines, and construction, mining, and agricultural machines; liquid filter systems comprising liquid filter housing and replaceable filter elements for liquid filters as parts of motors, engines, and construction, mining, and agricultural machines; filter elements for liquid filters for the aforesaid liquid filters and liquid filter systems; filters for electric discharge machines; filter elements for the aforesaid filters for electric discharge machines; liquid filters for construction, mining, and agricultural machine tools; filters for gaseous substances for motors, engines, and construction, mining, and agricultural machines; air filters as parts of motors, engines, and construction, mining, and agricultural machines; air filter systems comprising air filter housing and replaceable air filter elements as parts of motors, engines, and construction, mining, and agricultural machines; air filter elements for the aforesaid air filters and air filter systems; intake-air filters as parts of air-intake systems for motors, engines and construction, mining, and agricultural machines; dust separators; air intake systems for motors, engines, and construction, mining, and agricultural machines comprised of air filters, air intake ducts and valves; active air intake systems for motors, engines, and construction, mining, and agricultural machines comprised of air filters, air intake ducts, and valves; passive air intake systems for motors, engines, and construction, mining, and agricultural machines comprised of air filters, air intake ducts, and valves; intake manifolds for motors and engines; active intake manifolds for motors and engines; passive intake manifolds for motors and engines; filters for internal combustion engines; filter systems comprising filter housing and replaceable filter elements for internal combustion engines; filter elements for the aforesaid filters and filter systems for internal combustion engines; filters for land vehicles, namely, fuel filters, in-line fuel filters, in-tank fuel filters, oil filters, gear oil filters, urea filters, and engine and motor filters, namely, filters for hydraulic fluids, filters for coolants, cooling water filters, spin-on filters, air filters, intake-air filters, aeration filters, and ventilation filters; filter systems comprising filter housing and replaceable filter elements, for land vehicle motors and engines; filter elements for the aforesaid filters and filter systems for land vehicle motors and engines; air ducts being parts of motors, engines, and machines; clean side air ducts being parts of motors, engines, and machines; dirty side air ducts being parts of motors, engines, and machines