The grease stays in the tool cavity, not on your hands. - Press down on the cap until the old grease is forced out and the new grease shows on top of the bearing.
Lisle 34550 Handy Packer
Lisle Tools "Handy Packer" Bearing Packer #34550
Lisle Corporation 34550 Handy Packer Bearing Packer Tool
Lisle Handy Packer Bearing Grease Packer Tool 34550 Wheel Bearings up to 3 1/2"
Lisle Tools 34550 Handy Bearing Packer For Up To 3-1/2in Bearings
Premium Bearing Packer Kit, Handy Wheel Tool Portable Wheel...