OMC Vitabitz Rig Rings from One More Cast are a useful addition when building a dynamic Hair Rig presentation, often called a Blow Back Rig. Adding a Rig Ring lets the Hair pivot and move up and down the hook shank, giving the hook greater movement to flip underwater and catch hold in the fish's mouth. - 2.5mm Vitabitz Rig Ring is suited to Size 6 Hooks and smaller. - 3mm Vitabitz Rig Ring is suited to Size 4 Hooks and larger.