The HMH Jaws are interchangeable and allow you to swap out jaws. Each jaw can be twisted in or out. The Omni is a standard jaw that holds hooks from 2/0 to 22. The Micro Jaw holds hooks from 16-28. The Magnum is a for saltwater/bass/streamer hooks from 8-4/0 (larger hooks may be used, depending on the thickness of the wire ).