Fish-Field Saltwater Trolling Rollers are designed for making trolling rigs and lures for saltwater fishing, like tuna clones and marlin skirts. This roller allows you to quickly exchange the double hooks. Also a good way to protect the leader loops. It is 24K gold plated and comes with 6pc in a pack. Works with both mono and fluorocarbon line from 80lb to 400lb. Preferred by both sport and commercial anglers.