What is a Snap Swivel?

Snap swivels have a safety-pin like clip linked to one of the rings. Lures may be affixed directly to the snap. The presence of the swivel has been said to detract from the effectiveness of some types of lures. Depending on the position of the lure, the hooks can become entangled in various ways with the swivel.

It is also noted that swivels can serve as weak points in the line, and therefore lessen the likelihood of landing larger or harder fighting fish.