The Black Nickel plating assists to reduce the visibility of these heavy duty brass swivels, avoiding many of the bite-offs that occur with standard brass products that may produce a reflection, attracting fish away from the sharp end of the rig. They complement the low-vis terminal-gear approach, where fluorocarbon leaders and small hooks are now the norm for finesse fishing.
When it comes to sizing Swimerz Rolling Swivels match them to the strength of the leader you’re using. If you’re not stealth fishing and can get away with a slightly stronger and larger swivel than your leader, you’ll get that much more insurance against line twist. Swimerz Rolling Swivels are good for various rigs and leader trace making, and provide a high level of performance when fishing freshwater, saltwater, and offshore.