GROZ PROLUBE 44847 Deluxe Steel Bearing Packer. Rugged steel construction ideal for greasing bearings in cars, boats, tractors, and RV's. Nonthreaded top cone for fast and easy placement of bearings. The design incorporates grease nipples on the outer shaft which adapts to the grease gun coupler. Suited for bearings with a min ID of 1/2-inch to max 6-inch and height from 3/8-inch o 2-inch. USEFUL TIPS: Always use the recommended grade of grease. Some grades of grease can't handle temperatures of wheel bearing applications. Don't use compressed air for cleaning the bearing before use with bearing packer.