Without Bearing (WOB) Precision CNC machined from marine grade aluminum. Hard anodized finish for superb corrosion resistance. Pin, Axle, Screws, and Rollers all made from SS316 Stainless steel for superb resistance to corrosion. Includes two high grade Japanese stainless steel ball bearings used with each roller guide. Guide feet are pre-ground then anodized for easy wrapping. Perfect for use on rods up to the 80lb class. As the guides get smaller in size, the guide feet get narrower in width so it fits the blank better towards the tip of the rod. TC models feature rollers that are plated with DLC (Diamond Like Carbon) physical vapor deposition coating. DLC is extremely hard and slick and helps lower the coefficient friction between the roller and your line.