The Mustad Rolling Diamond Eye Swivel with J-snap is a very strong, dependable and easy way to change your lure. It features great strength for its size. The diamond shaped eye of the swivel, guides the line to stay centered, keeping knot in-line for maximum rotation. The rolling swivel design makes them perform better when under load, with the swivels still able to spin and reduce line twist when placed under considerable pressure. When choosing a swivel always go small. Pick a swivel, which will match the breaking strength of your line. This will give the best performance and presentation. Made from brass, for either saltwater or freshwater use.