Magnetic filters for floury substances protect subsequent machines from damage as a result of ferrous particles, thus fulfilling the quality demands of food appliances. The magnetic fitter's cylindrical form allows it to be installed, with customized couplings, directly between the silo outlet (tankers) and the connecting hose to the supply station. The rapidly flowing product-air mixture is distributed by a sieve. Ferrous particles are attracted by bar magnets with a particularly strong magnetic field. The sorted metallic particles can be removed by opening the dustproof doors.