Rollers are made from a high end polymer material and are a very good performance upgrade for your standard JR secondary. They eliminate helix ramp wear.
This material is very resilient to high load wear and is extremely smooth and slippery. Special roller curvature for smoother and very repeatable shifts. These roller kits are supplied with their own custom fasteners, and all components are CNC machined, which means they are a direct bolt up replacement for the OEM rollers using basic hand tools.