Type F / K F / K Standard typeIndustry top level Quality. Model K/F (magnetic drum diameter: φ140 mm for models 4 to 18 and φ216 mm for models 24 to 36) Model F Ferrite Magnet An economical, general-purpose type. improved adherence power due to an efficient design (magnet arrangement and shape). Works well with all sludge except difficult magnetized sludge Model K Rare Earth Magnet 10 Times the Magnetic Energy Rare earth permanent magnets are used,which compared to ferrite magnets, have10 times the magnetic energy ferrite one. removal of difficult magnetized sludge, or high viscosity coolant is possible