If you'd prefer to have your pigment cups in a convenient location at all times, and the workspace next to your client isn't cutting it, pigment cup rings are what you're looking for. They sit on your fingers ready to go whenever you are.
These particular cup rings have a detachable cup with a sponge insert. This pulls the ink up into the sponge, allowing you to dip your needle without touching the bottom and damaging your sterile needle.
These pigment cup rings are used to dispense small amounts of pigment during a cosmetic tattoo procedure.