Follower plates eliminate channeling and air pockets, keep lubricant free from contaminants, remove all grease from the drum and aid pump prime. HD follower plates are manufactured in galvanized steel and has a central part in aluminum that adjusts to the pump tube using O’ring to create a perfect seal. For PM45 & PM60 grease pumps, Application: 50 kg - 120 lb. Max. - min. drum diameter: 370 - 330 mm