Dorman Help 46341 Universal Bearing Packer Hand-Operated Grease Gun or Power Lube Equipment Size: Services Bearings having a minimum of 1/2″ I.D (12.5 mm) to a maximum O.D. of 4-1/2″ (113 mm) Universal – for use on all Grease GunsLightweight yet, Rugged ConstructionThreaded Center Post for Positive LockingEasily Lubricates most BearingsPrimes easily and pumps efficiently when using Heavy Greases at Low-TemperaturesCan be used with either Hand-Operated Grease Guns or Hydraulic Power Lube EquipmentIdeal for use on Car, Light Truck, Farm Vehicle, Boat, Trailer and RV Bearings.